DEFINITION aplus_asucc()
TYPE =
∀g:G.∀h:nat.∀a:A.(eq A (aplus g (asucc g a) h) (asucc g (aplus g a h)))
BODY =
assume g: G
assume h: nat
assume a: A
(h1)
by (refl_equal . .)
we proved eq A (asucc g (aplus g a h)) (asucc g (aplus g a h))
eq A (aplus g a (plus (S O) h)) (asucc g (aplus g a h))
end of h1
(h2)
by (aplus_assoc . . . .)
eq A (aplus g (aplus g a (S O)) h) (aplus g a (plus (S O) h))
end of h2
by (eq_ind_r . . . h1 . h2)
we proved eq A (aplus g (aplus g a (S O)) h) (asucc g (aplus g a h))
that is equivalent to eq A (aplus g (asucc g a) h) (asucc g (aplus g a h))
we proved ∀g:G.∀h:nat.∀a:A.(eq A (aplus g (asucc g a) h) (asucc g (aplus g a h)))