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%I #17 Jan 03 2024 23:44:07
%S 195,88979085,40601334443475,18526470109137550365,
%T 8453665363699081172206755,3857424412768091666931149169645,
%U 1760150474386452098440318147235146035,803160181759629441009745959552760456892925,366483597255522282717242648737403383853920317315
%N Numbers Y such that 237*Y^2+79 is a square.
%H Vincenzo Librandi, <a href="/A145305/b145305.txt">Table of n, a(n) for n = 1..180</a>
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (456302,-1).
%F a(n+2) = 456302*a(n+1)-a(n).
%F G.f.: 195*x*(x+1) / (x^2-456302*x+1). - _Colin Barker_, Oct 20 2014
%e a(1)=195 because the first relation is : 3002^2=237*195^2+79.
%t CoefficientList[Series[195 (x + 1)/(x^2 - 456302 x + 1), {x, 0, 20}], x] (* _Vincenzo Librandi_, Oct 21 2014 *)
%t LinearRecurrence[{456302,-1},{195,88979085},20] (* _Harvey P. Dale_, Jan 19 2020 *)
%o (PARI) Vec(195*x*(x+1)/(x^2-456302*x+1) + O(x^20)) \\ _Colin Barker_, Oct 20 2014
%o (Magma) I:=[195,88979085]; [n le 2 select I[n] else 456302*Self(n-1)-Self(n-2): n in [1..10]]; // _Vincenzo Librandi_, Oct 21 2014
%K easy,nonn
%O 1,1
%A _Richard Choulet_, Oct 06 2008
%E Editing and more terms from _Colin Barker_, Oct 20 2014
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