```    G4 Prover
Result of the test for sequent X@X@p(X) <--> X@p(X)

G4 Prover: a Prolog Prover for Roy Dyckhoff's Sequent Calculus G4
This prover is a fork made by Joseph Vidal-Rosset (joseph.vidal-rosset@gmail.com),
from seqprover.pl, the sequent prover for CL-X, written by Naoyuki Tamura (tamura@kobe-u.ac.jp).
Type "help." if you need some help.
fol(g4i)> fol(g4i).
yes
fol(g4i)> output(pretty).
yes
fol(g4i)> _5580@_5580@p(_5580)<-->_5580@p(_5580).
Trying to prove with threshold = 0 1
Succeed in proving _5580@_5580@p(_5580) --> _5580@p(_5580) (50 msec.)
pretty:1 =
-------------------------- Ax
X@p(X),X@X@p(X) --> X@p(X)
-------------------------- L@
X@X@p(X) --> X@p(X)
Trying to prove with threshold = 0 1
Succeed in proving _14840@p(_14840) --> _14840@_14840@p(_14840) (6278 msec.)
pretty:2 =
-------------------- Ax
p(Z),X@p(X) --> p(Z)
-------------------- L@
X@p(X) --> p(Z)
----------------- R@
X@p(X) --> Y@p(Y)
------------------- R@
X@p(X) --> X@X@p(X)
yes
fol(g4i)> quit.
yes
Exit from Sequent Calculus Prover...
Total CPU time = 6331 msec.
true

Back to g4-prover
Maintained by  Joseph Vidal-Rosset
```