MAYBE

Initial complexity problem:
1:	T:
		(?, 1)    ack(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(?, 1)    ack(a, b) -> ack(a, b - 1) [ a >= 1 /\ b >= 1 ]
		(1, 1)    start(a, b) -> ack(a, b)
	start location:	start
	leaf cost:	0

A polynomial rank function with
	Pol(ack) = V_1
	Pol(start) = V_1
orients all transitions weakly and the transition
	ack(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
strictly and produces the following problem:
2:	T:
		(a, 1)    ack(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(?, 1)    ack(a, b) -> ack(a, b - 1) [ a >= 1 /\ b >= 1 ]
		(1, 1)    start(a, b) -> ack(a, b)
	start location:	start
	leaf cost:	0

By chaining the transition start(a, b) -> ack(a, b) with all transitions in problem 2, the following new transitions are obtained:
	start(a, b) -> ack(a, b - 1) [ a >= 1 /\ b >= 1 ]
	start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
We thus obtain the following problem:
3:	T:
		(1, 2)    start(a, b) -> ack(a, b - 1) [ a >= 1 /\ b >= 1 ]
		(1, 2)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(a, 1)    ack(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(?, 1)    ack(a, b) -> ack(a, b - 1) [ a >= 1 /\ b >= 1 ]
	start location:	start
	leaf cost:	0

By chaining the transition start(a, b) -> ack(a, b - 1) [ a >= 1 /\ b >= 1 ] with all transitions in problem 3, the following new transitions are obtained:
	start(a, b) -> ack(a, b - 2) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 ]
	start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 ]
We thus obtain the following problem:
4:	T:
		(1, 3)    start(a, b) -> ack(a, b - 2) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 ]
		(1, 3)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 ]
		(1, 2)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(a, 1)    ack(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(?, 1)    ack(a, b) -> ack(a, b - 1) [ a >= 1 /\ b >= 1 ]
	start location:	start
	leaf cost:	0

By chaining the transition start(a, b) -> ack(a, b - 2) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 ] with all transitions in problem 4, the following new transitions are obtained:
	start(a, b) -> ack(a, b - 3) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 ]
	start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 ]
We thus obtain the following problem:
5:	T:
		(1, 4)    start(a, b) -> ack(a, b - 3) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 ]
		(1, 4)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 ]
		(1, 3)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 ]
		(1, 2)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(a, 1)    ack(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(?, 1)    ack(a, b) -> ack(a, b - 1) [ a >= 1 /\ b >= 1 ]
	start location:	start
	leaf cost:	0

By chaining the transition start(a, b) -> ack(a, b - 3) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 ] with all transitions in problem 5, the following new transitions are obtained:
	start(a, b) -> ack(a, b - 4) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 ]
	start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 ]
We thus obtain the following problem:
6:	T:
		(1, 5)    start(a, b) -> ack(a, b - 4) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 ]
		(1, 5)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 ]
		(1, 4)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 ]
		(1, 3)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 ]
		(1, 2)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(a, 1)    ack(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(?, 1)    ack(a, b) -> ack(a, b - 1) [ a >= 1 /\ b >= 1 ]
	start location:	start
	leaf cost:	0

By chaining the transition start(a, b) -> ack(a, b - 4) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 ] with all transitions in problem 6, the following new transitions are obtained:
	start(a, b) -> ack(a, b - 5) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 ]
	start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 ]
We thus obtain the following problem:
7:	T:
		(1, 6)    start(a, b) -> ack(a, b - 5) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 ]
		(1, 6)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 ]
		(1, 5)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 ]
		(1, 4)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 ]
		(1, 3)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 ]
		(1, 2)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(a, 1)    ack(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(?, 1)    ack(a, b) -> ack(a, b - 1) [ a >= 1 /\ b >= 1 ]
	start location:	start
	leaf cost:	0

By chaining the transition start(a, b) -> ack(a, b - 5) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 ] with all transitions in problem 7, the following new transitions are obtained:
	start(a, b) -> ack(a, b - 6) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 ]
	start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 ]
We thus obtain the following problem:
8:	T:
		(1, 7)    start(a, b) -> ack(a, b - 6) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 ]
		(1, 7)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 ]
		(1, 6)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 ]
		(1, 5)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 ]
		(1, 4)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 ]
		(1, 3)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 ]
		(1, 2)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(a, 1)    ack(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(?, 1)    ack(a, b) -> ack(a, b - 1) [ a >= 1 /\ b >= 1 ]
	start location:	start
	leaf cost:	0

By chaining the transition start(a, b) -> ack(a, b - 6) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 ] with all transitions in problem 8, the following new transitions are obtained:
	start(a, b) -> ack(a, b - 7) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 ]
	start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 ]
We thus obtain the following problem:
9:	T:
		(1, 8)    start(a, b) -> ack(a, b - 7) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 ]
		(1, 8)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 ]
		(1, 7)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 ]
		(1, 6)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 ]
		(1, 5)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 ]
		(1, 4)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 ]
		(1, 3)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 ]
		(1, 2)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(a, 1)    ack(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(?, 1)    ack(a, b) -> ack(a, b - 1) [ a >= 1 /\ b >= 1 ]
	start location:	start
	leaf cost:	0

By chaining the transition start(a, b) -> ack(a, b - 7) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 ] with all transitions in problem 9, the following new transitions are obtained:
	start(a, b) -> ack(a, b - 8) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 ]
	start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 ]
We thus obtain the following problem:
10:	T:
		(1, 9)    start(a, b) -> ack(a, b - 8) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 ]
		(1, 9)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 ]
		(1, 8)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 ]
		(1, 7)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 ]
		(1, 6)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 ]
		(1, 5)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 ]
		(1, 4)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 ]
		(1, 3)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 ]
		(1, 2)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(a, 1)    ack(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(?, 1)    ack(a, b) -> ack(a, b - 1) [ a >= 1 /\ b >= 1 ]
	start location:	start
	leaf cost:	0

By chaining the transition start(a, b) -> ack(a, b - 8) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 ] with all transitions in problem 10, the following new transitions are obtained:
	start(a, b) -> ack(a, b - 9) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 ]
	start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 ]
We thus obtain the following problem:
11:	T:
		(1, 10)    start(a, b) -> ack(a, b - 9) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 ]
		(1, 10)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 ]
		(1, 9)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 ]
		(1, 8)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 ]
		(1, 7)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 ]
		(1, 6)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 ]
		(1, 5)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 ]
		(1, 4)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 ]
		(1, 3)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 ]
		(1, 2)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(a, 1)     ack(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(?, 1)     ack(a, b) -> ack(a, b - 1) [ a >= 1 /\ b >= 1 ]
	start location:	start
	leaf cost:	0

By chaining the transition start(a, b) -> ack(a, b - 9) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 ] with all transitions in problem 11, the following new transitions are obtained:
	start(a, b) -> ack(a, b - 10) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 ]
	start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 ]
We thus obtain the following problem:
12:	T:
		(1, 11)    start(a, b) -> ack(a, b - 10) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 ]
		(1, 11)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 ]
		(1, 10)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 ]
		(1, 9)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 ]
		(1, 8)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 ]
		(1, 7)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 ]
		(1, 6)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 ]
		(1, 5)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 ]
		(1, 4)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 ]
		(1, 3)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 ]
		(1, 2)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(a, 1)     ack(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(?, 1)     ack(a, b) -> ack(a, b - 1) [ a >= 1 /\ b >= 1 ]
	start location:	start
	leaf cost:	0

By chaining the transition start(a, b) -> ack(a, b - 10) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 ] with all transitions in problem 12, the following new transitions are obtained:
	start(a, b) -> ack(a, b - 11) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 ]
	start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 ]
We thus obtain the following problem:
13:	T:
		(1, 12)    start(a, b) -> ack(a, b - 11) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 ]
		(1, 12)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 ]
		(1, 11)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 ]
		(1, 10)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 ]
		(1, 9)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 ]
		(1, 8)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 ]
		(1, 7)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 ]
		(1, 6)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 ]
		(1, 5)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 ]
		(1, 4)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 ]
		(1, 3)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 ]
		(1, 2)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(a, 1)     ack(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(?, 1)     ack(a, b) -> ack(a, b - 1) [ a >= 1 /\ b >= 1 ]
	start location:	start
	leaf cost:	0

By chaining the transition start(a, b) -> ack(a, b - 11) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 ] with all transitions in problem 13, the following new transitions are obtained:
	start(a, b) -> ack(a, b - 12) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 ]
	start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 ]
We thus obtain the following problem:
14:	T:
		(1, 13)    start(a, b) -> ack(a, b - 12) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 ]
		(1, 13)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 ]
		(1, 12)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 ]
		(1, 11)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 ]
		(1, 10)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 ]
		(1, 9)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 ]
		(1, 8)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 ]
		(1, 7)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 ]
		(1, 6)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 ]
		(1, 5)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 ]
		(1, 4)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 ]
		(1, 3)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 ]
		(1, 2)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(a, 1)     ack(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(?, 1)     ack(a, b) -> ack(a, b - 1) [ a >= 1 /\ b >= 1 ]
	start location:	start
	leaf cost:	0

By chaining the transition start(a, b) -> ack(a, b - 12) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 ] with all transitions in problem 14, the following new transitions are obtained:
	start(a, b) -> ack(a, b - 13) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 /\ b - 12 >= 1 ]
	start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 /\ b - 12 >= 1 ]
We thus obtain the following problem:
15:	T:
		(1, 14)    start(a, b) -> ack(a, b - 13) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 /\ b - 12 >= 1 ]
		(1, 14)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 /\ b - 12 >= 1 ]
		(1, 13)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 ]
		(1, 12)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 ]
		(1, 11)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 ]
		(1, 10)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 ]
		(1, 9)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 ]
		(1, 8)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 ]
		(1, 7)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 ]
		(1, 6)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 ]
		(1, 5)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 ]
		(1, 4)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 ]
		(1, 3)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 ]
		(1, 2)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(a, 1)     ack(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(?, 1)     ack(a, b) -> ack(a, b - 1) [ a >= 1 /\ b >= 1 ]
	start location:	start
	leaf cost:	0

By chaining the transition start(a, b) -> ack(a, b - 13) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 /\ b - 12 >= 1 ] with all transitions in problem 15, the following new transitions are obtained:
	start(a, b) -> ack(a, b - 14) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 /\ b - 12 >= 1 /\ b - 13 >= 1 ]
	start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 /\ b - 12 >= 1 /\ b - 13 >= 1 ]
We thus obtain the following problem:
16:	T:
		(1, 15)    start(a, b) -> ack(a, b - 14) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 /\ b - 12 >= 1 /\ b - 13 >= 1 ]
		(1, 15)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 /\ b - 12 >= 1 /\ b - 13 >= 1 ]
		(1, 14)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 /\ b - 12 >= 1 ]
		(1, 13)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 ]
		(1, 12)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 ]
		(1, 11)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 ]
		(1, 10)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 ]
		(1, 9)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 ]
		(1, 8)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 ]
		(1, 7)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 ]
		(1, 6)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 ]
		(1, 5)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 ]
		(1, 4)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 ]
		(1, 3)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 ]
		(1, 2)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(a, 1)     ack(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(?, 1)     ack(a, b) -> ack(a, b - 1) [ a >= 1 /\ b >= 1 ]
	start location:	start
	leaf cost:	0

By chaining the transition start(a, b) -> ack(a, b - 14) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 /\ b - 12 >= 1 /\ b - 13 >= 1 ] with all transitions in problem 16, the following new transitions are obtained:
	start(a, b) -> ack(a, b - 15) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 /\ b - 12 >= 1 /\ b - 13 >= 1 /\ b - 14 >= 1 ]
	start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 /\ b - 12 >= 1 /\ b - 13 >= 1 /\ b - 14 >= 1 ]
We thus obtain the following problem:
17:	T:
		(1, 16)    start(a, b) -> ack(a, b - 15) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 /\ b - 12 >= 1 /\ b - 13 >= 1 /\ b - 14 >= 1 ]
		(1, 16)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 /\ b - 12 >= 1 /\ b - 13 >= 1 /\ b - 14 >= 1 ]
		(1, 15)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 /\ b - 12 >= 1 /\ b - 13 >= 1 ]
		(1, 14)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 /\ b - 12 >= 1 ]
		(1, 13)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 /\ b - 11 >= 1 ]
		(1, 12)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 /\ b - 10 >= 1 ]
		(1, 11)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 /\ b - 9 >= 1 ]
		(1, 10)    start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 /\ b - 8 >= 1 ]
		(1, 9)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 /\ b - 7 >= 1 ]
		(1, 8)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 /\ b - 6 >= 1 ]
		(1, 7)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 /\ b - 5 >= 1 ]
		(1, 6)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 /\ b - 4 >= 1 ]
		(1, 5)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 /\ b - 3 >= 1 ]
		(1, 4)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 /\ b - 2 >= 1 ]
		(1, 3)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 /\ b - 1 >= 1 ]
		(1, 2)     start(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(a, 1)     ack(a, b) -> ack(a - 1, c) [ a >= 1 /\ b >= 1 ]
		(?, 1)     ack(a, b) -> ack(a, b - 1) [ a >= 1 /\ b >= 1 ]
	start location:	start
	leaf cost:	0

Complexity upper bound ?

Time: 2.379 sec (SMT: 2.226 sec)