A012407 sech(arctan(x)*log(x+1)) = 1 - 12/4!*x^4 + 60/5!*x^5 - 90/6!*x^6 + 420/7!*x^7...

1, 0, 0, 0, -12, 60, -90, 420, -4928, -32256, 788760, -4052400, 12074568, -397549152, 2860681824, 80960836320, -1570434928128, 8575093540224, -83967092441280, 3671889608928384, -27749577690072192

Offset

0,5

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Mathematica

Range[0, 20]! CoefficientList[ Series[ Sech[ArcTan[x] Log[x + 1]], {x, 0, 20}], x] (* Robert G. Wilson v, Nov 13 2011 *)

Crossrefs

Sequence in context: A359419 A372135 A012658 * A009093 A012400 A009172

Adjacent sequences: A012404 A012405 A012406 * A012408 A012409 A012410

Keyword

sign

Author

Patrick Demichel (patrick.demichel(AT)hp.com)

Status

approved