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 A158184 #4 Mar 31 2012 12:35:26 %S A158184 1,4,9,25,49,121,225,484,900,1764,3136,5929,10201,18225,30976,53361, %T A158184 88209,148225,240100,393129,627264,1004004,1575025,2480625,3833764, %U A158184 5934093,9060082,13823450,20838976,31404082,46810997,69700899,102868926 %N A158184 Number of nondecreasing integer sequences of length 50 with sum zero and sum of absolute values 2n. %C A158184 a(n) = A000041(n)^2 for n<=25 %C A158184 a(n) = A000041(n)^2 - cumulative A000712(2*n-1-length), 0 <= 2*n-1-length <= floor(n/2) [empirical]. %H A158184 R. H. Hardin, <a href="/A158184/b158184.txt">Table of n, a(n) for n=1..191</a> %K A158184 nonn %O A158184 1,2 %A A158184 _R. H. Hardin_ Mar 13 2009