eq(f3(A,B,C),1,[f4(A,B,D)],[0>=B]).
eq(f3(A,B,C),1,[f2(A,B,C,D,E,F,G),loop_cont_f2(E,F,G)],[D=0,B>=1]).
eq(f3(A,B,C),1,[f2(A,B,C,D,E,F,G)],[D=1,B>=1]).
eq(f2(A,B,C,D,E,F,G),1,[f2(-B+A,1+B,C,D,E,F,G)],[A>=1]).
eq(f2(A,B,C,D,A,B,E),1,[],[D=1,0>=A]).