A013554 Numerator of [x^(2n+1)] in the Taylor expansion -tan(cot(x)-coth(x))= 2*x/3 +8*x^3/81 +556*x^5/25515 +496*x^7/98415 +717572*x^9/613814355 +...

2, 8, 556, 496, 717572, 52939408, 870202072, 964225030112, 657454597470988, 27485377040128048, 700808303776317525176, 1479866177061564649568, 1640650015131154843789016, 13376815891310731844679270304, 25395222315410089406698868631728

Offset

0,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..100

Mathematica

Numerator[Take[CoefficientList[Series[- Tan[Cot[x] - Coth[x]], {x, 0, 35}], x], {2, -2, 2}]] (* Vincenzo Librandi, Nov 12 2016 *)

Crossrefs

Sequence in context: A221065 A023365 A262826 * A175923 A356202 A076985

Adjacent sequences: A013551 A013552 A013553 * A013555 A013556 A013557

Keyword

nonn,frac

Author

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

Extensions

Name edited by R. J. Mathar, Dec 21 2011

Status

approved