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A205961 Expansion of 1/(-32*x^5 + 8*x^3 - 4*x^2 - x + 1). 2
1, 1, 5, 1, 13, 9, 85, 177, 477, 921, 1701, 4289, 9389, 28201, 60917, 153041, 308349, 733625, 1645125, 4062177, 9670989, 22625865, 52288405, 118067953, 276204317, 639640537, 1523941861 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Previous name was: Expand 1/(1 - x/2 - x^2 + x^3 - x^5) in powers of x, then multiply coefficient of x^n by 2^n to get integers.

The sequence is from -1 + x^2 - x^3 - x^4/2 + x^5 with real root 1.1647612555333289.

The limiting ratio of successive terms is 2*1.1647612555333289.

Recurrence: -32 *a (n) + 8 *a (n + 2) - 4 *a (n + 4) + a (n + 5) == 0; with a (1) == 1; a (2) == 1; a (3) == 5; a (4) == 1; a (5) == 13 (from FindSequenceFunction[]).

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (1,4,-8,0,32).

MATHEMATICA

CoefficientList[Series[1/(1 - x/2 - x^2 + x^3 - x^5), {x, 0, 50}], x] * 2^Range[0, 50]

LinearRecurrence[{1, 4, -8, 0, 32}, {1, 1, 5, 1, 13}, 100] (* G. C. Greubel, Nov 16 2016 *)

PROG

(PARI) for(n=0, 30, print1(2^n*polcoeff(1/(1-x/2 - x^2 + x^3 - x^5) + O(x^32), n), ", ")) \\ G. C. Greubel, Nov 16 2016

CROSSREFS

Cf. A202907, A167602, A167602, A117791, A107293, A204631, A185357.

Sequence in context: A243883 A147004 A319664 * A146620 A300291 A174504

Adjacent sequences:  A205958 A205959 A205960 * A205962 A205963 A205964

KEYWORD

nonn,easy,less

AUTHOR

Roger L. Bagula, Feb 02 2012

EXTENSIONS

New name from Joerg Arndt, Nov 19 2016

STATUS

approved

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Last modified August 20 18:56 EDT 2019. Contains 326154 sequences. (Running on oeis4.)