A102077 Denominators of e.g.f. cosec(arctanh(x)).

6, 12, 126, 72, 22, 252, 126, 144, 7182, 2772, 4554, 1512, 378, 84, 14322, 2464, 42, 14364, 342, 792, 1251558, 191268, 136206, 21168, 594, 1188, 33858, 1368, 1062, 257796, 128898, 576, 6407478, 17388, 295218, 948024, 79002, 158004, 89586, 14256

Offset

1,1

Links

Table of n, a(n) for n=1..40.

Example

cosec(arctanh(x)) = 1/x - x/6 - 1/12*x^3/3! + 125/126x^5/5! +...
cosech(arctan(x)) = 1/x + x/6 - 1/12*x^3/3! - 125/126x^5/5! +...

Maple

G:=series(csc(arctanh(x)), x=0, 92): seq(denom((2*n-1)!*coeff(G, x^(2*n-1))), n=1..45); # Emeric Deutsch, Feb 25 2005

Crossrefs

Numerators are in A102076. Probably differs from A102062.

Sequence in context: A335735 A051586 A228858 * A102062 A164584 A156432

Adjacent sequences: A102074 A102075 A102076 * A102078 A102079 A102080

Keyword

nonn,frac

Author

Ralf Stephan, Dec 31 2004

Extensions

More terms from Emeric Deutsch, Feb 25 2005

Status

approved