diff options
Diffstat (limited to 'mathcomp/ssreflect/seq.v')
| -rw-r--r-- | mathcomp/ssreflect/seq.v | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mathcomp/ssreflect/seq.v b/mathcomp/ssreflect/seq.v index 74b3f15..5566a44 100644 --- a/mathcomp/ssreflect/seq.v +++ b/mathcomp/ssreflect/seq.v @@ -1453,7 +1453,7 @@ Definition perm_eq s1 s2 := Lemma permP s1 s2 : reflect (count^~ s1 =1 count^~ s2) (perm_eq s1 s2). Proof. apply: (iffP allP) => /= [eq_cnt1 a | eq_cnt x _]; last exact/eqP. -elim: {a}_.+1 {-2}a (ltnSn (count a (s1 ++ s2))) => // n IHn a le_an. +have [n le_an] := ubnP (count a (s1 ++ s2)); elim: n => // n IHn in a le_an *. have [/eqP|] := posnP (count a (s1 ++ s2)). by rewrite count_cat addn_eq0; do 2!case: eqP => // ->. rewrite -has_count => /hasP[x s12x a_x]; pose a' := predD1 a x. |