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%I #23 Apr 17 2024 16:06:57
%S 1,361,116281,37442161,12056259601,3882078149401,1250017107847561,
%T 402501626648765281,129604273763794572961,41732173650315203728201,
%U 13437630311127731805907801,4326875228009479326298583761,1393240385788741215336338063281
%N Squares of the form 5n*(n-1)+1.
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (323,-323,1).
%F a(n) = A049683(2*n-1) = (1/16) * (Lucas(12*n-6) - 2). - _Joerg Arndt_, Apr 09 2023
%F From _Chai Wah Wu_, Apr 17 2024: (Start)
%F a(n) = 323*a(n-1) - 323*a(n-2) + a(n-3) for n > 3.
%F G.f.: x*(-x^2 - 38*x - 1)/((x - 1)*(x^2 - 322*x + 1)). (End)
%o (PARI) for(n=1,10^8,x=(5*n*(n-1)+1); if(issquare(x),print(x)))
%Y Bisection of A049683.
%Y Cf. A062786.
%K nonn,easy,changed
%O 1,2
%A _Jason Earls_, Jul 19 2001
%E More terms from _Sean A. Irvine_, Apr 08 2023
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