A102074 Denominators of e.g.f. sec(arccosh(x)) = cosec(arcsinh(x)).

3, 3, 63, 9, 11, 63, 63, 9, 3591, 693, 2277, 189, 189, 21, 7161, 77, 21, 3591, 171, 99, 625779, 47817, 68103, 1323, 297, 297, 16929, 171, 531, 64449, 64449, 99, 3203739, 4347, 147609, 118503, 39501, 39501, 44793, 891, 913, 208593, 29799, 15939

Offset

1,1

Links

Table of n, a(n) for n=1..44.

Example

sec(arccosh(x)) = 1/x + x/3 - 1/3*x^3/3! + 220/63*x^5/5! -...

Mathematica

t = Denominator[(Range[90] - 1)!CoefficientList[ Series[ Csc[ ArcSinh[x]], {x, 0, 90}], x]]; Table[ t[[n]], {n, 2, 90, 2}] (* Robert G. Wilson v, Jan 12 2005 *)

Crossrefs

Numerators are in A102073. Differs from A102065.

Sequence in context: A051752 A332786 A102065 * A126227 A333827 A213137

Adjacent sequences: A102071 A102072 A102073 * A102075 A102076 A102077

Keyword

nonn,frac

Author

Ralf Stephan, Dec 31 2004

Extensions

Corrected and extended by Robert G. Wilson v, Jan 12 2005

Status

approved