A260535 a(n) = (2*n+1)!*Sum_{k=0..n} B(2*k), B(n) the n-th Bernoulli number.

1, 7, 136, 5832, 407808, 47882880, 5893585920, 2763273139200, -1770980740300800, 6081299047511654400, -24479310471391641600000, 147692341217380307927040000, -1254349086918655739874508800000, 14641717268146696857494972006400000, -229475387530005564381034470860390400000

Offset

0,2

Comments

It appears that for n > 6, a(n)*(-1)^n < 0. (This comment was inspired by an observation of Robert Israel in A061053.)

Links

Table of n, a(n) for n=0..14.

Maple

a := n -> (2*n+1)!*add(bernoulli(2*k), k=0..n): seq(a(n), n=0..30);

Mathematica

Table[(2 n + 1)! Sum[BernoulliB[2 k], {k, 0, n}], {n, 0, 14}] (* Michael De Vlieger, Sep 21 2015 *)

Crossrefs

Cf. A061053.

Sequence in context: A368630 A210028 A243684 * A220380 A051504 A058881

Adjacent sequences: A260532 A260533 A260534 * A260536 A260537 A260538

Keyword

sign

Author

Peter Luschny, Sep 21 2015

Status

approved