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 A026275 #4 Mar 30 2012 18:56:05 %S A026275 2,4,11,21,28,43,53,73,96,111,139,170,190,226,249,290,334,362,411,442, %T A026275 496,553,589,651,716,757,827,871,946,1024,1073,1156,1242,1296,1387, %U A026275 1444,1540,1639,1701,1805,1870,1979,2091,2161,2278 %N A026275 Sum of numbers between the two n's in A026272. %K A026275 nonn %O A026275 1,1 %A A026275 _Clark Kimberling_