fact: Fixpoint inscode (c : seq nat) (i : 'I_n) := if c is c0 :: c' then let m := size c' in if i > m - c0 then c0 :: inscode c' (inord i.-1) else if i == m - c0 :> nat then c0.-1 :: c' else if i.+1 == m - c0 :> nat then c0.+1 :: c' else c0 :: inscode c' i else [::].
imports: HB(structures) mathcomp(all_ssreflect) mathcomp(fingroup perm morphism presentation) mathcomp(ssralg poly ssrint) permcomp tools permuted combclass congr