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%I #17 Jul 06 2023 20:54:41
%S 43,318157,2353725443,17412860509157,128820339693018043,
%T 953012855636086972957,7050388977175431732917843,
%U 52158776700130988324039229557,385870622977180074445810487344843,2854670816626401490619117661337918957
%N x-values in the solution to the Pell equation x^2 - 74*y^2 = -1.
%C All terms are multiples of 43.
%H Colin Barker, <a href="/A228546/b228546.txt">Table of n, a(n) for n = 1..250</a>
%H Christian Aebi and Grant Cairns, <a href="http://math.colgate.edu/~integers/x48/x48.pdf">Lattice equable quadrilaterals III: tangential and extangential cases</a>, Integers (2023) Vol. 23, #A48.
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (7398,-1).
%F a(n) = 7398*a(n-1)-a(n-2).
%F G.f.: 43*x*(x+1) / (x^2-7398*x+1).
%t LinearRecurrence[{7398,-1},{43,318157},10] (* _Harvey P. Dale_, Oct 13 2017 *)
%o (PARI) Vec(43*x*(x+1)/(x^2-7398*x+1) + O(x^30))
%Y Cf. A228547 gives the corresponding y-values.
%K nonn,easy
%O 1,1
%A _Colin Barker_, Aug 25 2013
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