A013546 - OEIS

A013546

Numerator of [x^(2n)] in the Taylor expansion cosh(cosec(x)-coth(x))=1 +x^2/72 -215*x^4/31104 +199159*x^6/235146240-...

1, 1, -215, 199159, -4128623, 257347648013, -111384981593, 1407269115959761, 69849267671401979, 467410556088873329284747, 429563383515510620615310131, 652256640736921402479041889329, 137438707390027290209533044701, 432938003151091640246284451153923, 5720446637387424876679468922735017734533

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OFFSET

0,3

COMMENTS

A bisection of A013536. Denominators are a bisection of A202382.

LINKS

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

MATHEMATICA

Numerator[Take[CoefficientList[Series[Cosh[Csc[x] - Coth[x]], {x, 0, 35}], x], {1, -2, 2}]] (* Vincenzo Librandi, Nov 12 2016 *)

CROSSREFS

Sequence in context: A002239 A375180 A322929 * A192073 A372208 A018863

Adjacent sequences: A013543 A013544 A013545 * A013547 A013548 A013549