fact: Definition perm_of_setpart P : {perm T} := (\prod_(C in [set perm_of_porbit s | s in [set X in P |#|X|>1]]) C)%g.
imports: mathcomp.ssreflect.ssreflect mathcomp(ssrfun ssrbool eqtype ssrnat seq choice fintype) mathcomp(tuple finfun finset path bigop) mathcomp(fingroup perm action) mathcomp(ssralg matrix mxalgebra algC classfun) partition tools sorted permcomp fibered_set cycles