A262127 Number of permutations p of [2n] such that the up-down signature of p has nonnegative partial sums with a maximal value of n.

1, 1, 3, 57, 778, 47673, 1477381, 196352061, 10896848134, 2539183745028, 220995092995233, 79875004816604671, 10032237471596350240, 5198811549997063847059, 890008776794671492878641, 626002734896306246681963237, 140112228518254335504033414806

Offset

0,3

Links

Alois P. Heinz, Table of n, a(n) for n = 0..50

Formula

a(n) = A262125(2n,n).

Crossrefs

Cf. A262125.

Sequence in context: A131466 A171356 A060483 * A139746 A273919 A157929

Adjacent sequences: A262124 A262125 A262126 * A262128 A262129 A262130

Keyword

nonn

Author

Alois P. Heinz, Sep 11 2015

Status

approved