A228579 x-values in the solution to the Pell equation x^2 - 106*y^2 = -1.

4005, 256961212515, 16486657605006072525, 1057785633576265066862185035, 67867634144387774982257006782401045, 4354394329202601312629024169108475989921555, 279378384309860411015977934462690086320911158397565

Offset

1,1

Comments

All terms are multiples of 4005.

Links

Colin Barker, Table of n, a(n) for n = 1..120

Index entries for linear recurrences with constant coefficients, signature (64160102,-1).

Formula

a(n) = 64160102*a(n-1)-a(n-2).

G.f.: 4005*x*(x+1) / (x^2-64160102*x+1).

Mathematica

LinearRecurrence[{64160102, -1}, {4005, 256961212515}, 20] (* Harvey P. Dale, Apr 05 2018 *)

Prog

(PARI) Vec(4005*x*(x+1)/(x^2-64160102*x+1) + O(x^30))

Crossrefs

Cf. A228580 gives the corresponding y-values.

Sequence in context: A218641 A092722 A034306 * A252328 A235307 A386240

Adjacent sequences: A228576 A228577 A228578 * A228580 A228581 A228582

Keyword

nonn,easy

Author

Colin Barker, Aug 26 2013

Status

approved