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A174776 y-values in the solution to  x^2 - 39*y^2 = 1. 2
0, 4, 200, 9996, 499600, 24970004, 1248000600, 62375059996, 3117504999200, 155812874900004, 7787526240001000, 389220499125149996, 19453237430017498800, 972272651001749790004, 48594179312657472001400 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The corresponding values of x of this Pell equation are in  A174751.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..200

Index entries for linear recurrences with constant coefficients, signature (50,-1).

FORMULA

a(n) = 50*a(n-1)-a(n-2) with a(1)=0, a(2)=4.

G.f.: 4*x^2/(1-50*x+x^2).

MATHEMATICA

LinearRecurrence[{50, -1}, {0, 4}, 30]

PROG

(MAGMA) I:=[0, 4]; [n le 2 select I[n] else 50*Self(n-1)-Self(n-2): n in [1..20]];

CROSSREFS

Cf. A174751.

Sequence in context: A297061 A156235 A034862 * A216932 A317273 A049656

Adjacent sequences:  A174773 A174774 A174775 * A174777 A174778 A174779

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Apr 15 2010

STATUS

approved

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Last modified June 24 05:09 EDT 2021. Contains 345416 sequences. (Running on oeis4.)