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A152594 a(n)=-5*a(n-1)-2*a(n-2), n>1 ; a(0)=1, a(1)=-1 . 2
1, -1, 3, -13, 59, -269, 1227, -5597, 25531, -116461, 531243, -2423293, 11053979, -50423309, 230008587, -1049196317, 4785964411, -21831429421, 99585218283, -454263232573, 2072145726299, -9452202166349, 43116719379147 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..22.

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

FORMULA

G.f.: (1+4*x)/(1+5*x+2*x^2). a(n)=Sum_{k, 0<=k<n}A147703(n,k)*(-2)^(n-k). a(n)=(-1)^n*A052984(n-1), n>=1 ; a(0)=1.

a(n)=(1/2)*{[ -(5/2)-(1/2)*sqrt(17)]^n+[ -(5/2)+(1/2)*sqrt(17)]^n}+(3/34)*sqrt(17)*{[ -(5/2)+(1/2)*sqrt(17)]^n-[ -(5/2)-(1/2)*sqrt(17)]^n}, with n>=0 [From Paolo P. Lava, Dec 12 2008]

MATHEMATICA

LinearRecurrence[{-5, -2}, {1, -1}, 30] (* Harvey P. Dale, Jun 18 2015 *)

CROSSREFS

Sequence in context: A151228 A268596 A199297 * A052984 A262664 A151229

Adjacent sequences:  A152591 A152592 A152593 * A152595 A152596 A152597

KEYWORD

sign

AUTHOR

Philippe Deléham, Dec 09 2008

STATUS

approved

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Last modified April 3 15:16 EDT 2020. Contains 333197 sequences. (Running on oeis4.)