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 A256512 #6 Aug 05 2021 12:28:03
%S A256512 0,3,34,651,16388,500005,17915910,737894535,34359738376,1785233613321,
%T A256512 102400000000010,6427501315524619,438244169232678924,
%U A256512 32254987351648575501,2548827677619195478030,215233605000000000000015,19342813113834066795298832
%N A256512 n*(1+(2*n)^n).
%C A256512 a(n) = A108396(2*n,n): central terms of the triangle A108396.
%H A256512 Reinhard Zumkeller, <a href="/A256512/b256512.txt">Table of n, a(n) for n = 0..250</a>
%t A256512 Join[{0},Table[n(1+(2n)^n),{n,20}]] (* _Harvey P. Dale_, Aug 05 2021 *)
%o A256512 (Haskell)
%o A256512 a256512 n = n * (1 + (2 * n) ^ n)
%Y A256512 Cf. A062971, A108396, A108398.
%K A256512 nonn
%O A256512 0,2
%A A256512 _Reinhard Zumkeller_, Mar 31 2015