def perm_self

bend-collections-laws-math@1.0.0.0 · proofs/math/natural/proof.bend:91

import Base
import bend-collections-laws-math@1.0.0.0/src/math/natural.bend as M
import bend-collections-laws-math@1.0.0.0/spec/math/natural.bend as S
import bend-collections-laws-math@1.0.0.0/proofs/math/natural/fact.bend as F

91def perm_self(+n: Nat) -> S.Perm.self(n):
92  Equal.trans(Nat, M.perm(n, n), S.desc(n, n), S.factorial(n), F.perm_ok(n, n), F.desc_self(n))