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%I #16 Jan 03 2024 23:45:45
%S 11,16005,23271259,33836394581,49198094449515,71533995493200229,
%T 104010380249018683451,151231021348077672537525,
%U 219889801029724686850877899,319719619466198346603503927621,464872106814051366236807859883035
%N Numbers Y such that 273*Y^2+91 is a square.
%H Vincenzo Librandi, <a href="/A145526/b145526.txt">Table of n, a(n) for n = 1..200</a>
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (1454,-1).
%F a(n+2) = 1454*a(n+1)-a(n).
%F G.f.: 11*x*(x+1) / (x^2-1454*x+1). - _Colin Barker_, Oct 21 2014
%e a(1)=11 because the first relation is : 182^2=273*11^2+91.
%t CoefficientList[Series[11 (x + 1)/(x^2 - 1454 x + 1), {x, 0, 20}], x] (* _Vincenzo Librandi_, Oct 21 2014 *)
%o (PARI) Vec(11*x*(x+1)/(x^2-1454*x+1) + O(x^20)) \\ _Colin Barker_, Oct 21 2014
%o (Magma) I:=[11,16005]; [n le 2 select I[n] else 1454*Self(n-1)-Self(n-2): n in [1..15]]; // _Vincenzo Librandi_, Oct 21 2014
%K easy,nonn
%O 1,1
%A _Richard Choulet_, Oct 12 2008
%E Editing from _Colin Barker_, Oct 21 2014
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