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 A047092 #4 Mar 30 2012 18:56:53 %S A047092 1,2,4,19,60,237,850,3252,12168,46497,177052,679745,2612226,10079515, %T A047092 38961906,150982379,586067980,2278999145,8874984360,34609160383, %U A047092 135125659144,528166347564,2066529185116,8093134894351 %N A047092 T(n,n-1), array T as in A047089. %K A047092 nonn %O A047092 1,2 %A A047092 _Clark Kimberling_