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%I #14 Sep 08 2022 08:45:51
%S 0,6,420,29394,2057160,143971806,10075969260,705173876394,
%T 49352095378320,3453941502606006,241726553087042100,
%U 16917404774590340994,1183976607668236827480,82861445132001987582606
%N y-values in the solution to x^2 - 34*y^2 = 1.
%C The corresponding values of x of this Pell equation are in A174749.
%H Vincenzo Librandi, <a href="/A174773/b174773.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 (70,-1).
%F a(n) = 70*a(n-1)-a(n-2) with a(1)=0, a(2)=6.
%F G.f.: 6*x^2/(1-70*x+x^2).
%t LinearRecurrence[{70,-1}, {0,6}, 30]
%o I:=[0, 6]; [n le 2 select I[n] else 70*Self(n-1)-Self(n-2): n (Magma) in [1..20]];
%o (PARI) a(n)=([0,1; -1,70]^(n-1)*[0;6])[1,1] \\ _Charles R Greathouse IV_, Jan 29 2016
%Y Cf. A174749.
%K nonn,easy
%O 1,2
%A _Vincenzo Librandi_, Apr 15 2010
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