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%I #17 Jul 06 2023 20:54:49
%S 5,36985,273615025,2024203917965,14975060311490045,
%T 110785494160199434945,819591070822095108233065,
%U 6063334631156365450508779925,44856548781703720780768845652085,331848741823709495179762469625344905
%N y-values in the solution to the Pell equation x^2 - 74*y^2 = -1.
%C All terms are multiples of 5.
%H Colin Barker, <a href="/A228547/b228547.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.: -5*(x-1) / (x^2-7398*x+1).
%t LinearRecurrence[{7398,-1},{5,36985},20] (* _Harvey P. Dale_, Jan 14 2015 *)
%o (PARI) Vec(-5*(x-1)/(x^2-7398*x+1) + O(x^30))
%Y Cf. A228546 gives the corresponding x-values.
%K nonn,easy
%O 1,1
%A _Colin Barker_, Aug 25 2013
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