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A099612 Numerators of coefficients in expansion of sec(x) + tan(x). 8
1, 1, 1, 1, 5, 2, 61, 17, 277, 62, 50521, 1382, 540553, 21844, 199360981, 929569, 3878302429, 6404582, 2404879675441, 443861162, 14814847529501, 18888466084, 69348874393137901, 113927491862, 238685140977801337, 58870668456604, 4087072509293123892361 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

LINKS

Table of n, a(n) for n=0..26.

L. Euler, On the sums of series of reciprocals, par. 13.

L. Euler, De summis serierum reciprocarum, E41, par. 13.

EXAMPLE

1 + x + 1/2*x^2 + 1/3*x^3 + 5/24*x^4 + 2/15*x^5 + 61/720*x^6 + 17/315*x^7 + ...

1, 1, 1/2, 1/3, 5/24, 2/15, 61/720, 17/315, 277/8064, 62/2835, 50521/3628800, 1382/155925, 540553/95800320, ... = A099612/A099617

MATHEMATICA

nn = 26; Numerator[CoefficientList[Series[Sec[x] + Tan[x], {x, 0, nn}], x]] (* T. D. Noe, Jul 24 2013 *)

CROSSREFS

Cf. A099617.

Sequence in context: A224494 A095998 A208927 * A233044 A142599 A068566

Adjacent sequences:  A099609 A099610 A099611 * A099613 A099614 A099615

KEYWORD

nonn,frac

AUTHOR

N. J. A. Sloane, Nov 18 2004

STATUS

approved

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Last modified December 18 12:28 EST 2014. Contains 252154 sequences.