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 A268015 #4 Jan 24 2016 09:54:44 %S A268015 27,729,19683,474552,10941048,240641848,5106219048,105087226959, %T A268015 2107490863661,41332013859375,794974954718853,15030454569975872, %U A268015 279880270014528000,5140991504979000000,93278442949595408448 %N A268015 Number of nX3 0..2 arrays with every repeated value in every row and column greater than or equal to the previous repeated value. %C A268015 Column 3 of A268019. %H A268015 R. H. Hardin, <a href="/A268015/b268015.txt">Table of n, a(n) for n = 1..210</a> %F A268015 Empirical: a(n) = 84*a(n-1) -2814*a(n-2) +45276*a(n-3) -285019*a(n-4) -1063944*a(n-5) +20124468*a(n-6) -1605816*a(n-7) -630123753*a(n-8) -402925572*a(n-9) +10392502302*a(n-10) +30566899188*a(n-11) +12457260613*a(n-12) -49186967088*a(n-13) -30986023080*a(n-14) +49186967088*a(n-15) +12457260613*a(n-16) -30566899188*a(n-17) +10392502302*a(n-18) +402925572*a(n-19) -630123753*a(n-20) +1605816*a(n-21) +20124468*a(n-22) +1063944*a(n-23) -285019*a(n-24) -45276*a(n-25) -2814*a(n-26) -84*a(n-27) -a(n-28) %e A268015 Some solutions for n=3 %e A268015 ..2..0..2....2..0..2....2..2..0....0..0..2....1..1..0....0..2..0....2..0..2 %e A268015 ..0..0..2....1..0..2....2..0..1....2..2..0....0..1..2....2..1..1....0..2..2 %e A268015 ..1..2..0....0..1..2....1..0..2....0..0..0....0..2..0....1..2..0....2..1..1 %Y A268015 Cf. A268019. %K A268015 nonn %O A268015 1,1 %A A268015 _R. H. Hardin_, Jan 24 2016