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A135949 a(n)=5a(n-2)+2a(n-3). 0
1, -1, 1, -3, 3, -13, 9, -59, 19, -277, -23, -1347, -669, -6781, -6039, -35243, -43757, -188293, -289271, -1028979, -1822941, -5723437, -11172663, -32263067, -67310189, -183660661, -401077079, -1052923683, -2372706717, -6066772573 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

Table of n, a(n) for n=0..29.

Index entries for linear recurrences with constant coefficients, signature (0, 5, 2).

FORMULA

a(n)=(5/14)*[1+sqrt(2)]^n+(2/7)*sqrt(2)*[1-sqrt(2)]^n+(2/7)*(-2)^n+(5/14)*[1-sqrt(2)]^n-(2/7) *[1+sqrt(2)]^n*sqrt(2), with n>=0 - Paolo P. Lava, Jun 09 2008

G.f.: (1-x-4x^2)/((1+2x)(1-2x-x^2)). [From R. J. Mathar, Feb 07 2009]

CROSSREFS

Sequence in context: A020550 A306529 A200921 * A168234 A141245 A147032

Adjacent sequences:  A135946 A135947 A135948 * A135950 A135951 A135952

KEYWORD

sign,easy

AUTHOR

Paul Curtz, Mar 02 2008

EXTENSIONS

More terms from R. J. Mathar, Feb 07 2009

STATUS

approved

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Last modified July 28 23:26 EDT 2021. Contains 346340 sequences. (Running on oeis4.)