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 A134856 #8 Sep 25 2013 02:24:56 %S A134856 2880,27720,40320,49920,63360,98280,241920,282744,491400,547200, %T A134856 604800,950400,970200,1048320,1370880,1614600,1774080,2489760,2608320, %U A134856 2882880,2923200,3931200,4817400,6126120,7338240,7673400,8426880,10200960 %N A134856 Numbers that can be written as (a^2-1)(b^2-1) in three or more distinct ways. %C A134856 Contains A134857 and A134858 as subsequences. %H A134856 MathPages, <a href="http://www.mathpages.com/home/kmath275.htm">Numbers Expressible As (a^2-1)(b^2-1)</a>. %e A134856 2880 = (2^2-1)(31^2-1) = (3^2-1)(19^2-1) = (5^2-1)(11^2-1). %Y A134856 Cf. A134857, A134858, A057535, A063066, A063067, A063068. %K A134856 easy,nonn %O A134856 1,1 %A A134856 _Herman Beeksma_, Nov 13 2007