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 A047134 #7 Jan 20 2020 07:57:38 %S A047134 1,3,9,28,76,235,768,1679,5564,19613,126070,437604,1610354,6015427, %T A047134 27167487,104861750,403189070,1550582656,6369655714,25112303442, %U A047134 98241919002,383342448413,1531690132421,6058160780203,23859853900666 %N A047134 T(n,n-2), array T as in A047130. %K A047134 nonn %O A047134 2,2 %A A047134 _Clark Kimberling_ %E A047134 Definition corrected by _Georg Fischer_, Jan 20 2020