fact: Definition starFnext (y : 'rV[letter]_n) M : {set 'I_n} := [set n0 | (y ``_ n0 == Star) && [forall m0, (m0 \in `F n0) ==> (M m0 n0 == Star)]].
imports: mathcomp(all_ssreflect ssralg fingroup finalg perm zmodp) mathcomp(matrix) f2 ssr_ext ssralg_ext max_subset num_occ hamming ldpc_erasure tanner linearcode