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A013536
Numerators of coefficients in Taylor series expansion of exp(cosec(x)-cotanh(x)).
4
1, -1, 1, 53, -215, 3341, 199159, 391337, -4128623, 710371933, 257347648013, 6178130243, -111384981593, 225570264096917, 1407269115959761, 1546226961439379, 69849267671401979, 5665951032145572087083, 467410556088873329284747, -1602619428542796266047, 429563383515510620615310131, 218332153959703843484481031721
OFFSET
0,4
LINKS
EXAMPLE
1 -1/6*x+1/72*x^2 +53/1296*x^3 -215/31104*x^4 +3341/6531840*x^5 +199159/235146240*x^6 +...
MAPLE
t1:=exp(csc(x)-coth(x));
t2:=series(t1, x, 30);
t3:=seriestolist(t2);
t4:=map(numer, t3); t5:=map(denom, t3); lprint(t2);
MATHEMATICA
Numerator[CoefficientList[Series[Exp[Csc[x]-Coth[x]], {x, 0, 30}], x]](* N. J. A. Sloane, Feb 28 2014 *)
CROSSREFS
Cf. A202382.
Sequence in context: A005146 A158644 A158656 * A142000 A053652 A142316
KEYWORD
sign,frac
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
EXTENSIONS
Corrected by N. J. A. Sloane, Dec 18 2011, based on discussions on the Sequence Fans Mailing List, Dec 13-17 2011.
Mathematica program modified by Harvey P. Dale, Feb 28 2014
STATUS
approved