YES(?, 2*a + 2*b + 2*c + 1)

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

A polynomial rank function with
	Pol(f) = V_1 - V_2 - V_3
	Pol(start) = V_1 - V_2 - V_3
orients all transitions weakly and the transitions
	f(a, b, c) -> f(a, b + 1, c) [ a >= b + c + 1 ]
	f(a, b, c) -> f(a, b, c + 1) [ a >= b + c + 1 ]
strictly and produces the following problem:
2:	T:
		(a + b + c, 1)    f(a, b, c) -> f(a, b + 1, c) [ a >= b + c + 1 ]
		(a + b + c, 1)    f(a, b, c) -> f(a, b, c + 1) [ a >= b + c + 1 ]
		(1, 1)            start(a, b, c) -> f(a, b, c)
	start location:	start
	leaf cost:	0

Complexity upper bound 2*a + 2*b + 2*c + 1

Time: 0.095 sec (SMT: 0.091 sec)