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A279257 Numerators of coefficients in expansion of 1/(cos x - sin x). 2
1, 1, 3, 11, 19, 361, 307, 24611, 83579, 2873041, 12193841, 512343611, 869783713, 11779156811, 769881545161, 44110959165011, 299540369626699, 19450718635716001, 16510282817165209, 10784052561125704811, 8321625562774808569, 7342627959965776406281 (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. A279258.

Sequence in context: A192598 A028978 A082628 * A166096 A139220 A139221

Adjacent sequences:  A279254 A279255 A279256 * A279258 A279259 A279260

KEYWORD

nonn,easy,frac

AUTHOR

Clark Kimberling, Dec 11 2016

STATUS

approved

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Last modified June 12 16:05 EDT 2021. Contains 344959 sequences. (Running on oeis4.)