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 A027146 #7 Oct 24 2019 16:04:55 %S A027146 1,8,30,224,880,6656,27104,206336,859392,6565888,27765760,212615168, %T A027146 908943360,6970998784,30045757440,230691307520,1000634122240, %U A027146 7689454223360,33522958204928,257783270211584,1128501249835008,8682602001072128,38141362595430400,293587672402755584 %N A027146 a(n) = A027144(2n, n-1). %K A027146 nonn %O A027146 1,2 %A A027146 _Clark Kimberling_ %E A027146 More terms from _Sean A. Irvine_, Oct 24 2019