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 A027093 #7 Oct 23 2019 17:17:50 %S A027093 1,1,5,17,57,190,623,2010,6395,20103,62561,193062,591637,1802551, %T A027093 5465275,16503365,49665179,149033583,446131159,1332749213,3974445543, %U A027093 11834777320,35196098205,104558824915,310332568225,920350334943 %N A027093 a(n) = A027082(n, 2n-6). %K A027093 nonn %O A027093 3,3 %A A027093 _Clark Kimberling_