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A228555
y-values in the solution to the Pell equation x^2 - 85*y^2 = -1.
2
41, 23433017, 13392859670105, 7654528230109038473, 4374853755566666771111369, 2500395165741407064797340577049, 1429070852233137457244575771954319993, 816768296741122520872908940486430799582185
OFFSET
1,1
COMMENTS
All terms are multiples of 41.
FORMULA
a(n) = 571538*a(n-1)-a(n-2).
G.f.: -41*x*(x-1) / (x^2-571538*x+1).
MATHEMATICA
LinearRecurrence[{571538, -1}, {41, 23433017}, 20] (* Harvey P. Dale, Nov 29 2017 *)
PROG
(PARI) Vec(-41*x*(x-1)/(x^2-571538*x+1) + O(x^30))
CROSSREFS
Cf. A228554 gives the corresponding x-values.
Sequence in context: A297230 A087512 A297055 * A297058 A125194 A237639
KEYWORD
nonn,easy
AUTHOR
Colin Barker, Aug 25 2013
STATUS
approved