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%I #21 Jun 13 2015 00:51:47
%S 0,24,48,3576,7080,522144,1033704,76229520,150913776,11128987848,
%T 22032377664,1624755996360,3216576225240,237203246480784,
%U 469598096507448,34630049230198176,68558105513862240,5055749984362452984
%N Numbers n such that 37*n^2 + 37*n + 1 is a square.
%H <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (1,146,-146,-1,1).
%F Define a(1)=0, a(2)=24, a(3)=146*a(1)+72-a(2), a(4)=146*a(2)+72-a(1), then a(n) = 146*a(n-2)+72-a(n-4).
%F G.f.: -24*x^2*(x^2+x+1)/(x^5-x^4-146*x^3+146*x^2+x-1). [_Harvey P. Dale_, Mar 14 2011]
%t CoefficientList[Series[-((24x(x^2+x+1))/(x^5-x^4-146x^3 +146x^2+x-1)), {x,0,30}],x] (* _Harvey P. Dale_, Mar 14 2011 *)
%Y Cf. A105843 (square roots of 37*a(n)^2+37*a(n)+1).
%K nonn,easy
%O 1,2
%A _Pierre CAMI_, Apr 22 2005
%E More terms from _Harvey P. Dale_, Mar 14 2011
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