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%I #17 Jan 17 2024 09:56:47
%S 7,170107,4133940307,100463017170607,2441452239146151007,
%T 59332172215266744601507,1441890446733960188159672107,
%U 35040821577196528277389606942807,851562044527139583463162039764423607,20694660771057724580125235612965415554507
%N Numbers n such that there exists x in N : (x+1)^3-x^3=31*n^2.
%H Michael De Vlieger, <a href="/A145322/b145322.txt">Table of n, a(n) for n = 1..228</a>
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (24302,-1).
%F a(n+2) = 24302*a(n+1)-a(n).
%F G.f.: -7*x*(x-1) / (x^2-24302*x+1). - _Colin Barker_, Oct 19 2014
%e a(1)=7 because 23^3-22^3=31*7^2.
%t LinearRecurrence[{24302, -1}, {7, 170107}, 10] (* _Paolo Xausa_, Jan 17 2024 *)
%o (PARI) Vec(-7*x*(x-1)/(x^2-24302*x+1) + O(x^20)) \\ _Colin Barker_, Oct 19 2014
%K easy,nonn
%O 1,1
%A _Richard Choulet_, Oct 07 2008
%E Editing and a(10) from _Colin Barker_, Oct 19 2014
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