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%I #13 Jun 13 2015 00:51:47
%S 1,37,2927,68171,183769,4280053,338355383,7880431259,21243328861,
%T 494765566657,39113205561107,910962092609711,2455686329490109,
%U 57193909970135833,4521408336114491603,105305395973616940919,283872428295154291321,6611501604232996456477
%N Numbers n such that n^2 = 19*m^2 + 19*m + 1.
%H <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,0,115598,0,0,0,-1).
%F Define a(1)=0, a(2)=39, a(3)=2927, a(4)=68171, a(5)=115598*a(1)+a(4), a(6)=115598*a(2)+a(3), a(7)=115598*a(3)+a(2), a(8)=115598*a(4)+a(1) then a(n)=115598*a(n-4)-a(n-8).
%F G.f.: x*(x+1)*(x^6+36*x^5+2891*x^4+65280*x^3+2891*x^2+36*x+1) / ((x^4-340*x^2+1)*(x^4+340*x^2+1)). - _Colin Barker_, Mar 06 2013
%Y Cf. A101180 (associated m).
%K nonn,easy
%O 1,2
%A _Pierre CAMI_, Apr 22 2005
%E a(13)-a(18) from _Colin Barker_, Mar 06 2013
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