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 A250659 #7 Nov 15 2018 15:04:28 %S A250659 159,286,445,636,859,1114,1401,1720,2071,2454,2869,3316,3795,4306, %T A250659 4849,5424,6031,6670,7341,8044,8779,9546,10345,11176,12039,12934, %U A250659 13861,14820,15811,16834,17889,18976,20095,21246,22429,23644,24891,26170,27481,28824 %N A250659 Number of (5+1) X (n+1) 0..1 arrays with nondecreasing x(i,j)-x(i,j-1) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction. %H A250659 R. H. Hardin, <a href="/A250659/b250659.txt">Table of n, a(n) for n = 1..210</a> %F A250659 Empirical: a(n) = 16*n^2 + 79*n + 64. %F A250659 Conjectures from _Colin Barker_, Nov 15 2018: (Start) %F A250659 G.f.: x*(159 - 191*x + 64*x^2) / (1 - x)^3. %F A250659 a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>3. %F A250659 (End) %e A250659 Some solutions for n=4: %e A250659 ..0..0..0..0..0....1..1..1..1..1....0..0..0..0..0....1..1..1..0..0 %e A250659 ..1..1..1..1..1....1..1..1..1..1....1..1..1..1..1....0..0..0..0..0 %e A250659 ..1..1..1..1..1....0..0..0..0..0....1..1..1..1..1....1..1..1..1..1 %e A250659 ..0..0..0..0..0....1..1..1..1..1....1..1..1..1..1....1..1..1..1..1 %e A250659 ..0..1..1..1..1....0..0..0..0..0....0..0..0..0..0....0..0..0..0..0 %e A250659 ..0..1..1..1..1....1..1..1..1..1....0..0..0..0..1....0..1..1..1..1 %Y A250659 Row 5 of A250656. %K A250659 nonn %O A250659 1,1 %A A250659 _R. H. Hardin_, Nov 26 2014