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 A278305 #4 Nov 17 2016 07:04:56 %S A278305 51,2089,70795,2360544,79562696,2506281752,69684770828,1689884963173, %T A278305 36045826631067,685286426542689,11759467817079518,184109136699624075, %U A278305 2653459164462630395,35466423366457631706,442375217765486649151 %N A278305 Number of nX4 0..2 arrays with rows and columns in lexicographic nondecreasing order but with exactly one mistake. %C A278305 Column 4 of A278309. %H A278305 R. H. Hardin, <a href="/A278305/b278305.txt">Table of n, a(n) for n = 1..210</a> %H A278305 R. H. Hardin, <a href="/A278305/a278305.txt">Empirical polynomial of degree 161</a> %F A278305 Empirical polynomial of degree 161 (see link above) %e A278305 Some solutions for n=3 %e A278305 ..0..1..2..1. .0..1..1..0. .0..0..2..2. .0..2..0..0. .0..1..1..1 %e A278305 ..1..0..0..1. .0..1..2..2. .2..2..1..2. .2..1..1..2. .1..2..0..0 %e A278305 ..1..1..1..1. .0..2..2..1. .0..1..2..2. .2..2..0..1. .2..1..2..2 %Y A278305 Cf. A278309. %K A278305 nonn %O A278305 1,1 %A A278305 _R. H. Hardin_, Nov 17 2016