None
Conclusion:
Alph:
.
R:Alph List
Alph List
.
Fin(Alph)
EquivRel(Alph List;x,y.x R y)
Fin(x,y:(Alph List)//(x R y))
(
x,y,z:Alph List. x R y
(z @ x) R (z @ y))
(
g:x,y:(Alph List)//(x R y)
.
x,y:x,y:(Alph List)//(x R y). Dec(x Rg y))
1. Dec(x Rg y)