A097322 - OEIS

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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

(list; graph; refs; listen; history; text; internal format)

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