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A132644 X-values of solutions to the equation X*(X + 1) - 13*Y^2 = 0. 0
0, 324, 421200, 546717924, 709639444800, 921111452633124, 1195601955878350800, 1551890417618646705924, 2014352566467047545939200, 2614628079383810095982376324, 3393785232687619037537578530000 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..10.

Index entries for linear recurrences with constant coefficients, signature (1299,-1299,1).

FORMULA

a(n) = 1298*a(n-1) - a(n-2) + 648; a(0)=0, a(1)=324.

a(n) = -1/2 + (1/4)*(649+180*sqrt(13))^n + (1/4)*(649-180*sqrt(13))^n, with n >= 0. - Paolo P. Lava, Oct 07 2008

G.f.: -324*x*(x+1)/((x-1)*(x^2 - 1298*x + 1)). - Colin Barker, Oct 25 2012

CROSSREFS

Cf. A007654.

Sequence in context: A298101 A209044 A209016 * A202635 A013763 A013887

Adjacent sequences:  A132641 A132642 A132643 * A132645 A132646 A132647

KEYWORD

nonn,easy

AUTHOR

Mohamed Bouhamida (bhmd95(AT)yahoo.fr), Nov 14 2007

EXTENSIONS

More terms from Paolo P. Lava, Oct 07 2008

STATUS

approved

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Last modified December 8 17:36 EST 2019. Contains 329865 sequences. (Running on oeis4.)