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 A027176 #7 Oct 24 2019 19:14:03 %S A027176 7,43,185,740,2900,11293,43897,170608,663438,2582058,10058862, %T A027176 39225116,153111686,598228961,2339499161,9157016216,35870666366, %U A027176 140623656686,551684484386,2165796506636,8507878418516,33441451138598 %N A027176 a(n) = A027170(2n-1, n-2). %K A027176 nonn %O A027176 2,1 %A A027176 _Clark Kimberling_