This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A051515 #7 Jul 02 2025 16:01:58 %S A051515 9,25,196,324,1089,1521,3600,4624,9025,11025,19044,22500,35721,41209, %T A051515 61504,69696,99225,110889,152100,168100,223729,245025,318096,345744, %U A051515 439569,474721,592900,636804,783225,837225,1016064,1081600,1297321 %N A051515 (Terms in A014738)/4. %H A051515 <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (1,4,-4,-6,6,4,-4,-1,1). %F A051515 From _Chai Wah Wu_, Feb 03 2021: (Start) %F A051515 a(n) = a(n-1) + 4*a(n-2) - 4*a(n-3) - 6*a(n-4) + 6*a(n-5) + 4*a(n-6) - 4*a(n-7) - a(n-8) + a(n-9) for n > 9. %F A051515 G.f.: x*(-9*x^6 - 16*x^5 - 135*x^4 - 64*x^3 - 135*x^2 - 16*x - 9)/((x - 1)^5*(x + 1)^4). (End) %Y A051515 A014738. %K A051515 nonn %O A051515 1,1 %A A051515 _James Sellers_