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 A014770 #16 Jan 23 2020 16:47:51 %S A014770 0,144,484,4900,8464,30976,44100,108900,141376,283024,348100,611524, %T A014770 725904,1166400,1350244,2033476,2310400,3312400,3709476,5116644, %U A014770 5664400,7573504,8305924,10824100,11778624,15023376,16240900,20340100 %N A014770 Squares of even pentagonal numbers. %F A014770 a(n) = A014633(n)^2. - _Sean A. Irvine_, Nov 20 2018 %F A014770 From _Chai Wah Wu_, Jan 23 2020: (Start) %F A014770 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 > 8. %F A014770 G.f.: -4*x*(x^7 + 168*x^6 + 227*x^5 + 1428*x^4 + 551*x^3 + 960*x^2 + 85*x + 36)/((x - 1)^5*(x + 1)^4). (End) %Y A014770 Cf. A014633. %Y A014770 Even terms of A100255. %K A014770 nonn,easy %O A014770 0,2 %A A014770 _Mohammad K. Azarian_ %E A014770 More terms from _Erich Friedman_. %E A014770 a(0)=0 inserted for consistency with A014633 by _Sean A. Irvine_, Nov 20 2018