YES
  TPA v.1.0

Result: TRS is terminating

Default interpretations for symbols are not printed. For polynomial interpretations
and semantic labelling over N\{0,1} defaults are 2 for constants, identity for unary
symbols and x+y-2 for binary symbols. For semantic labelling over {0,1} (booleans)
defaults are 0 for constants, identity for unary symbols and disjunction for binary symbols.

[1]  TRS loaded from input file:
(1) f(f(x)) -> f(x)
(2) f(s(x)) -> f(x)
(3) g(s(0)) -> g(f(s(0)))

[2]  Use following polynomial interpretation:
[s(x)] = x + 1
rest default

  Remove rules with left hand side strictly bigger than right hand side:
(2)

[3]  Label this TRS using following interpretation over N\{0,1}:
[f(x)] = 2
[s(x)] = x + 1
[g(x)] = 2
rest default

  This interpretation is a model and yields following TRS:
(1) f{2}(f{i}(x)) -> f{i}(x)
(3) g{3}(s{2}(0)) -> g{2}(f{3}(s{2}(0)))

[4]  Use following polynomial interpretation:
[f_{i}(x)] = x
[s_{i}(x)] = x
[g_{i}(x)] = x + i
rest default

  Remove rules with left hand side strictly bigger than right hand side:
(3)

[5]  Unlabel this TRS to obtain the one consisting of the rules:
(1)

[6]  Use following polynomial interpretation:
[f(x)] = x + 1
rest default

  Remove rules with left hand side strictly bigger than right hand side:
(1)

[7]  Since there are no remaining rules, termination is proved!

../tpdb/TRS/nontermin/AG01/#4.20a.trs, 0.01, Y
Couldn't open file <60>: 60: No such file or directory