A097322 (2n)! divided by denominator of Taylor expansion of exp(cos(x)-1).

1, 4, 1, 1, 4, 1, 1, 4, 1, 11, 4, 1, 1, 4, 11, 1, 4, 31, 1, 44, 29, 1, 4, 1, 11, 4, 29, 1, 4, 11, 1, 4, 31, 1, 1276, 1, 41, 4, 1, 11, 116, 1, 1, 292, 11, 1, 4, 31, 127571, 44, 1, 1, 4, 1, 319, 4, 41, 1, 4, 11, 1, 4, 899, 1, 44, 1, 1, 4, 29, 11, 4, 1, 1, 4, 583, 1, 4756, 361429

Offset

1,2

Links

Table of n, a(n) for n=1..78.

Prog

(PARI) a(n)=(2*n)!/denominator(polcoeff(Ser(exp(cos(x)-1)), 2*n))

Crossrefs

Equals A010050(n) / A047690(n).

Cf. A005046.

Sequence in context: A069289 A341309 A346778 * A177023 A214333 A343408

Adjacent sequences: A097319 A097320 A097321 * A097323 A097324 A097325

Keyword

nonn,easy

Author

Ralf Stephan, Aug 08 2004

Status

approved