fact: Definition summary_fold (X : {set 'I_n}) d e := foldr (fun i F t => \sum_(b in 'F_2) F (t `[ i := b ])) e (enum X) d.
imports: mathcomp(all_ssreflect ssralg fingroup finalg zmodp matrix) Reals mathcomp(Rstruct) ssr_ext ssralg_ext ssrR f2