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Numbers X such that (X^2-67)/201 is a square.
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%I #23 Apr 07 2024 17:12:02

%S 4154,4279405106,4408600346145986,4541695990591853912234,

%T 4678809792543413381498198474,4820063060175757335495037232017826,

%U 4965580763957784639661088992670945968466

%N Numbers X such that (X^2-67)/201 is a square.

%H Michael De Vlieger, <a href="/A145205/b145205.txt">Table of n, a(n) for n = 1..166</a>

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (1030190,-1).

%F a(n) = 1030190*a(n-1) - a(n-2).

%F G.f.: -4154*x*(x-1)/(x^2-1030190*x+1). - _Colin Barker_, Aug 24 2012

%F a(n) = 2*A145207(n)/67. - _Hugo Pfoertner_, Apr 07 2024

%e The first relation is : 4154^2=201*293^2+67.

%t LinearRecurrence[{1030190, -1}, {4154, 4279405106}, 10] (* _Paolo Xausa_, Jan 17 2024 *)

%Y Cf. A145207.

%K easy,nonn

%O 1,1

%A _Richard Choulet_, Oct 04 2008