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 A049719 #4 Mar 30 2012 18:56:56 %S A049719 11,19,30,43,62,81,104,133,162,193,230,267,310,359,406,459,510,571, %T A049719 630,695,764,829,910,983,1064,1145,1230,1325,1414,1513,1608,1707,1816, %U A049719 1923,2040,2153,2266,2389,2508,2645,2770,2903,3038 %N A049719 a(n)=T(n,n+3), array T as in A048149. %K A049719 nonn %O A049719 0,1 %A A049719 _Clark Kimberling_