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Revision History for A109088 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A109088

Taylor series of 1/f(x) with recursively defined function f(x) from A109087.
(history; published version)

#2 by N. J. A. Sloane at Fri Sep 29 03:00:00 EDT 2006

PROG

(PARI) N=40; f=x; g=1; for(n=1, N, g/=f; f+=g+O(x^N)); Vec(1/f)

KEYWORD

easy,sign,new

#1 by N. J. A. Sloane at Tue Jul 19 03:00:00 EDT 2005

NAME

Taylor series of 1/f(x) with recursively defined function f(x) from A109087.

DATA

0, 1, -1, -1, 4, -1, -11, 11, 26, -46, -70, 202, 160, -936, 252, 3119, -4379, -3459, 14888, -20536, 29732, 38061, -479128, 960501, 1356685, -8916019, 8540446, 35338281, -110022439, 5461908, 570854415, -1033426187, -1165212555, 7430011628, -6748665176, -27528038218, 81920080445, 10199574479

OFFSET

0,5

FORMULA

sum(n = 0, infinity)a(n)x^n = 1/f(x).

EXAMPLE

1/f(x) = x - x^2 - x^3 + 4*x^4 - x^5 - 11*x^6 + 11*x^7 + 26*x^8 - 46*x^9 - 70*x^10 + 202*x^11 + 160*x^12 - 936*x^13 + 252*x^14 + 3119*x^15 + O(x^16)

PROG

(PARI) N=40; f=x; g=1; for(n=1, N, g/=f; f+=g+O(x^N)); Vec(1/f)

CROSSREFS

Cf. A109086, A109089, A109090.

KEYWORD

easy,sign

AUTHOR

Nikolaus Meyberg (Nikolaus.Meyberg(AT)t-online.de), Jun 20 2005

STATUS

approved