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 A268249 #4 Jan 29 2016 07:37:00 %S A268249 2,9,4,60,81,8,570,3600,729,15,6960,324900,216000,6084,28,104006, %T A268249 48441600,185193000,12067722,49284,51,1837752,10817248036, %U A268249 337153536000,98956027822,648144348,386884,92,37478718,3377332413504,1125058699232216 %N A268249 T(n,k)=Number of nXk 0..k arrays with every repeated value in every row greater than, and every column greater than or equal to, the previous repeated value. %C A268249 Table starts %C A268249 ...2........9............60...............570.................6960 %C A268249 ...4.......81..........3600............324900.............48441600 %C A268249 ...8......729........216000.........185193000.........337153536000 %C A268249 ..15.....6084......12067722.......98956027822.....2213773305829075 %C A268249 ..28....49284.....648144348....50740994294843.13958709698552890082 %C A268249 ..51...386884...33600202086.25094770808231271 %C A268249 ..92..2965284.1691726672094 %C A268249 .164.22268961 %C A268249 .290 %H A268249 R. H. Hardin, <a href="/A268249/b268249.txt">Table of n, a(n) for n = 1..48</a> %F A268249 Empirical for column k: %F A268249 k=1: a(n) = 2*a(n-1) +a(n-2) -2*a(n-3) -a(n-4) %F A268249 k=2: [order 15] %e A268249 Some solutions for n=2 k=4 %e A268249 ..2..3..1..1....3..1..4..3....0..1..0..3....4..0..0..4....0..2..4..3 %e A268249 ..1..1..0..4....1..1..3..4....1..0..0..4....0..4..3..1....0..0..1..3 %Y A268249 Column 1 is A029907(n+1). %Y A268249 Column 2 is A268014. %Y A268249 Column 3 is A267977. %Y A268249 Row 1 is A268205. %Y A268249 Row 2 is A268206. %K A268249 nonn,tabl %O A268249 1,1 %A A268249 _R. H. Hardin_, Jan 29 2016