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%I
%S 1,301,90901,27451801,8290353001,2503659154501,756096774306301,
%T 228338722181348401,68957538001992910801,20824948137879677713501,
%U 6289065380101660676566501,1899276919842563644645369801
%N Numbers n such that there exists x in N : (x+1)^3-x^3=19*n^2
%C a(1)=1 because 3^3-2^3=19*1
%H <a href="/index/Rec#recLCC">Index to sequences with linear recurrences with constant coefficients</a>, signature (302,-1).
%F a(n+2)=302*a(n+1)-a(n)
%F a(n)=(1/2)*{[151+20*sqrt(57)]^n+[151-20*sqrt(57)]^n}-(5/76)*sqrt(57)*{[151-20 *sqrt(57)]^n-[151+20*sqrt(57)]^n}, with n>=0 [From _Paolo P. Lava_, Nov 25 2008]
%F G.f. -x*(-1+x) / ( 1-302*x+x^2 ). - R. J. Mathar, Nov 27 2011
%Y Cf. A145124.
%K easy,nonn
%O 1,2
%A _Richard Choulet_, Oct 02 2008
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