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 A278414 #4 Nov 21 2016 09:11:52 %S A278414 0,0,0,1,20,1,15,264,264,15,90,2550,9354,2550,90,357,22267,201539, %T A278414 201539,22267,357,1107,166762,3576730,11454780,3576730,166762,1107, %U A278414 2907,1046418,58069125,514122657,514122657,58069125,1046418,2907,6765,5586207 %N A278414 T(n,k)=Number of nXk 0..2 arrays with rows and columns in lexicographic nondecreasing order but with exactly two mistakes. %C A278414 Table starts %C A278414 .....0.........0.............1................15....................90 %C A278414 .....0........20...........264..............2550.................22267 %C A278414 .....1.......264..........9354............201539...............3576730 %C A278414 ....15......2550........201539..........11454780.............514122657 %C A278414 ....90.....22267.......3576730.........514122657...........62922179364 %C A278414 ...357....166762......58069125.......20086951472.........6584300364020 %C A278414 ..1107...1046418.....859516239......724313811311.......615691843257769 %C A278414 ..2907...5586207...11336482734....24378309172117.....53477639726024161 %C A278414 ..6765..25997719..132278417831...757386980723842...4387410446730955493 %C A278414 .14355.107862842.1373129978107.21490393664858691.339567886171232998387 %H A278414 R. H. Hardin, <a href="/A278414/b278414.txt">Table of n, a(n) for n = 1..127</a> %F A278414 Empirical for column k: %F A278414 k=1: [polynomial of degree 8] %F A278414 k=2: [polynomial of degree 26] %F A278414 k=3: [polynomial of degree 80] %e A278414 Some solutions for n=3 k=4 %e A278414 ..1..0..1..2. .0..0..0..0. .0..1..2..0. .0..1..1..2. .1..2..1..2 %e A278414 ..0..0..0..2. .1..1..0..1. .0..0..0..1. .0..1..0..2. .0..2..1..0 %e A278414 ..2..2..2..1. .0..2..1..1. .2..2..0..1. .2..0..0..2. .0..2..1..1 %Y A278414 Column 1 is A005716(n+1). %K A278414 nonn,tabl %O A278414 1,5 %A A278414 _R. H. Hardin_, Nov 21 2016