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A279258 Denominators of coefficients in expansion of 1/(cos x - sin x). 2
1, 1, 2, 6, 8, 120, 80, 5040, 13440, 362880, 1209600, 39916800, 53222400, 566092800, 29059430400, 1307674368000, 6974263296000, 355687428096000, 237124952064000, 121645100408832000, 73724303278080000, 51090942171709440000, 19719311013642240000 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

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

EXAMPLE

1/1 + (1/1)x + (3/2)x^2 + (11/6)x^3 + (19/8)x^3 + ... ; 1/1, 1/1, 3/2, 11/6, ... = A279257/A279258.

MATHEMATICA

z = 30; t = CoefficientList[Series[1/(Cos[x] - Sin[x]), {x, 0, z}], x];

Numerator[t]   (* A279257 *)

Denominator[t] (* A279258 *)

CROSSREFS

Cf. A279257.

Sequence in context: A002176 A329812 A124675 * A120709 A002689 A174727

Adjacent sequences:  A279255 A279256 A279257 * A279259 A279260 A279261

KEYWORD

nonn,easy,frac

AUTHOR

Clark Kimberling, Dec 11 2016

STATUS

approved

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Last modified June 22 16:01 EDT 2021. Contains 345386 sequences. (Running on oeis4.)