A279330 Numerators of coefficients in expansion of (cos(sqrt x))/(1 - x - x^2).

1, 1, 37, 1469, 28885, 20402009, 4408834189, 1292545686613, 502788842162641, 3827352937332721, 11769223393753084937, 6727141824232920032413, 6008596848623061712518761, 107427869448375950953038643849, 26282017131399910370907288078329

Offset

0,3

Links

Clark Kimberling, Table of n, a(n) for n = 0..1000

Example

(1/1) + (1/2)x + (37/24)x^2 + (1469/720)x^3 + ... ; 1/1, 1/2, 37/24, 1469/720, ... = A279330/A279331.

Mathematica

z = 30; t = CoefficientList[Series[Cos[Sqrt[x]]/(1 - x - x^2), {x, 0, z}], x];
Numerator[t]   (* A279330 *)
Denominator[t] (* A279331 *)

Crossrefs

Cf. A279331.

Sequence in context: A158741 A094490 A231543 * A009695 A201956 A322097

Adjacent sequences: A279327 A279328 A279329 * A279331 A279332 A279333

Keyword

nonn,easy,frac

Author

Clark Kimberling, Dec 11 2016

Status

approved