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A228535
x-values in the solution to the Pell equation x^2 - 53*y^2 = -1.
2
182, 24114818, 3195165155182, 423352992707189818, 56093424824522071350182, 7432266601976172417049224818, 984760460172545468089666118585182, 130478791444509662828968408963250219818, 17288178907829880845340110782723061506860182
OFFSET
1,1
COMMENTS
All terms are multiples of 182.
FORMULA
a(n) = 132498*a(n-1)-a(n-2).
G.f.: 182*x*(x+1) / (x^2-132498*x+1).
MATHEMATICA
CoefficientList[Series[182 (x + 1) / (x^2 - 132498 x + 1), {x, 0, 10}], x] (* Vincenzo Librandi, Aug 25 2013 *)
LinearRecurrence[{132498, -1}, {182, 24114818}, 20] (* Harvey P. Dale, Nov 07 2022 *)
PROG
(PARI) Vec(182*x*(x+1)/(x^2-132498*x+1) + O(x^50))
CROSSREFS
Cf. A228536 gives the corresponding y-values.
Sequence in context: A190830 A145525 A028676 * A248628 A217608 A264779
KEYWORD
nonn,easy
AUTHOR
Colin Barker, Aug 24 2013
STATUS
approved