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%I #22 Sep 08 2022 08:45:52
%S 1,251,126001,63252251,31752504001,15939693756251,8001694513134001,
%T 4016834705899512251,2016443020667042016001,1012250379540149192520251,
%U 508147674086134227603150001,255089120140859842107588780251
%N x-values in the solution to x^2-70*y^2=1.
%C The corresponding values of y of this Pell equation are in A176378.
%H Vincenzo Librandi, <a href="/A176377/b176377.txt">Table of n, a(n) for n = 1..200</a>
%H <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (502,-1).
%F a(n) = 502*a(n-1)-a(n-2) with a(1)=1, a(2)=251.
%F G.f.: x*(1-251*x)/(1-502*x+x^2). - _Harvey P. Dale_, Jun 14 2011
%t LinearRecurrence[{502,-1},{1,251},20] (* or *) CoefficientList[ Series[ (1-251 x)/(1-502 x+x^2),{x,0,20}],x] (* _Harvey P. Dale_, Jun 14 2011 *)
%o (PARI) Vec((1-251*x)/(1-502*x+x^2)+O(x^99)) \\ _Charles R Greathouse IV_, Jun 14 2011
%o (Magma) I:=[1, 251]; [n le 2 select I[n] else 502*Self(n-1)-Self(n-2): n in [1..20]];
%K nonn,easy
%O 1,2
%A _Vincenzo Librandi_, Apr 16 2010
%E Definition rewritten and g.f. adapted to the offset from _Bruno Berselli_, Dec 15 2011
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