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 A268105 #4 Jan 26 2016 12:20:20 %S A268105 4,81,4096,378225,56791296,12650850576,3926389806144,1621309443347169, %T A268105 859957083064464100,569966660957291549809,461690884178405990127504, %U A268105 448823671401604409584451856,515728792901852626366779599104 %N A268105 Number of 2Xn 0..n arrays with every repeated value in every row and column greater than or equal to the previous repeated value. %C A268105 Row 2 of A268103. %H A268105 R. H. Hardin, <a href="/A268105/b268105.txt">Table of n, a(n) for n = 1..26</a> %e A268105 Some solutions for n=5 %e A268105 ..0..0..0..5..5....0..0..0..3..0....0..0..0..3..4....0..0..1..1..0 %e A268105 ..0..3..5..2..3....0..0..3..0..4....0..0..1..3..3....0..3..4..3..4 %Y A268105 Cf. A268103. %K A268105 nonn %O A268105 1,1 %A A268105 _R. H. Hardin_, Jan 26 2016