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 A102306 #2 Apr 30 2014 01:31:35 %S A102306 7,9,13,14,18,19,21,26,27,28,31,35,36,37,39,42,43,45,49,52,54,56,57, %T A102306 61,62,63,65,67,70,72,73,74,76,77,78,79,81,84,86,90,91,93,95,97,98,99, %U A102306 103,104,105,108,109,111,112,114,117,119,122,124,126,127,129,130,133 %N A102306 Numbers k such that A083500(k) differs from A102305(k). %C A102306 What is the cardinality of a(n) with respect to its complement? %K A102306 nonn %O A102306 1,1 %A A102306 _Ralf Stephan_, Jan 03 2005