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%I #16 Mar 02 2024 01:28:55
%S 0,63,16128,4096575,1040514048,264286471743,67127723308800,
%T 17050177433963583,4330677940503441408,1099975146710440154175,
%U 279389356586511295719168,70963796597827158672514623
%N Values X satisfying the equation: X(X + 1) - 7*Y^2 = 0.
%C The full set of integer solutions to this equation consists of the pairs [X(i),Y(i)] = [1+-A001081(i), Y(i)=A001080(i)]. The present generates every second one of them: a(n) = [A001081(2n)-1]/2. - _R. J. Mathar_, Nov 20 2007
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (255, -255, 1).
%F a(0)=0, a(1)=63 and a(n)=254*a(n-1) - a(n-2) + 126.
%F G.f.: -63*x*(1+x)/(-1+x)/(1-254*x+x^2). a(n) = [A001081(2n)-1]/2. - _R. J. Mathar_, Nov 20 2007
%F a(0)=0, a(1)=63, a(2)=16128, a(n)=255*a(n-1)-255*a(n-2)+a(n-3). - _Harvey P. Dale_, Dec 15 2012
%t LinearRecurrence[{255,-255,1},{0,63,16128},20] (* _Harvey P. Dale_, Dec 15 2012 *)
%Y Cf. A007654.
%Y Cf. A001080, A001081.
%K nonn
%O 0,2
%A _Mohamed Bouhamida_, Nov 14 2007
%E More terms from _Max Alekseyev_, Nov 13 2009
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