A174755 x-values in the solution to x^2-47*y^2=1.

1, 48, 4607, 442224, 42448897, 4074651888, 391124132351, 37543842053808, 3603817713033217, 345928956609135024, 33205576016763929087, 3187389368652728057328, 305956173814645129574401

Offset

1,2

Comments

The corresponding values of y of this Pell equation are in A174853.

Links

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

Index entries for linear recurrences with constant coefficients, signature (96,-1).

Formula

a(n) = 96*a(n-1)-a(n-2) with a(1)=1, a(2)=48.

G.f.: x*(1-48*x)/(1-96*x+x^2).

Mathematica

LinearRecurrence[{96, -1}, {1, 48}, 30]

Prog

(Magma) I:=[1, 48]; [n le 2 select I[n] else 96*Self(n-1)-Self(n-2): n in [1..20]];

Crossrefs

Cf. A174853.

Sequence in context: A270253 A098209 A208793 * A269419 A299422 A321940

Adjacent sequences: A174752 A174753 A174754 * A174756 A174757 A174758

Keyword

nonn,easy

Author

Vincenzo Librandi, Apr 13 2010

Status

approved