Termination proof of /tmp/tmpQky7Jn/Ex4_7_77_Bor03

Termination of the following Term Rewriting System could not be shown:

Generalized rewrite system (where rules with free variables on rhs are allowed):
The TRS R consists of the following rules:

tail(cons(X)) → XS
zeros → cons(0)

↳ GTRS

Generalized rewrite system (where rules with free variables on rhs are allowed):
The TRS R consists of the following rules:

tail(cons(X)) → XS
zeros → cons(0)