NO

Prover = TRS(tech=GUIDED_UNF, nb_unfoldings=unlimited, unfold_variables=true, strategy=LEFTMOST_NE)

** BEGIN proof argument **
The following rule was generated while unfolding the analyzed TRS:
[iteration = 4] a__length(cons(_0,zeros)) -> a__length(cons(0,zeros))
Let l be the left-hand side and r be the right-hand side of this rule.
Let p = epsilon, theta1 = {} and theta2 = {_0->0}.
We have r|p = a__length(cons(0,zeros)) and theta2(theta1(l)) = theta1(r|p).
Hence, the term theta1(l) = a__length(cons(_0,zeros)) loops w.r.t. the analyzed TRS.
** END proof argument **

** BEGIN proof description **
## Searching for a generalized rewrite rule
(a rule whose right-hand side contains a variable
that does not occur in the left-hand side)...
No generalized rewrite rule found!

## Searching for a loop by unfolding (unfolding of variable subterms: ON)...
# Iteration 0: no loop detected, 3 unfolded rules generated.
# Iteration 1: no loop detected, 3 unfolded rules generated.
# Iteration 2: no loop detected, 7 unfolded rules generated.
# Iteration 3: no loop detected, 47 unfolded rules generated.
# Iteration 4: loop detected, 247 unfolded rules generated.
Here is the successful unfolding. Let IR be the TRS under analysis.
L0 = [a__length^#(cons(_0,_1)) -> a__U11^#(tt,_1), a__U11^#(tt,_2) -> a__U12^#(tt,_2), a__U12^#(tt,_3) -> a__length^#(mark(_3))] is in U_IR^0.
We merge the first and the second rule of L0.
==> L1 = [a__length^#(cons(_0,_1)) -> a__U12^#(tt,_1), a__U12^#(tt,_2) -> a__length^#(mark(_2))] is in U_IR^1.
We merge the first and the second rule of L1.
==> L2 = a__length^#(cons(_0,_1)) -> a__length^#(mark(_1)) is in U_IR^2.
Let p2 = [0].
We unfold the rule of L2 forwards at position p2
with the rule mark(zeros) -> a__zeros.
==> L3 = a__length^#(cons(_0,zeros)) -> a__length^#(a__zeros) is in U_IR^3.
Let p3 = [0].
We unfold the rule of L3 forwards at position p3
with the rule a__zeros -> cons(0,zeros).
==> L4 = a__length^#(cons(_0,zeros)) -> a__length^#(cons(0,zeros)) is in U_IR^4.

** END proof description **

Proof stopped at iteration 4
Number of unfolded rules generated by this proof = 307
Number of unfolded rules generated by all the parallel proofs = 1023