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 A273962 #3 Jun 05 2016 14:17:14 %S A273962 5,105,2766,49702,784878,13322548,232027264,4056338728,70402715640, %T A273962 1221782263634,21228810396872,368923543916728,6410003754557834, %U A273962 111371494441358332,1935130749075453956 %N A273962 Number of nX3 0..3 arrays with no three equal values forming an isosceles right triangle, and new values introduced in 0..3 order. %C A273962 Column 3 of A273964. %e A273962 Some solutions for n=4 %e A273962 ..0..1..2. .0..1..1. .0..1..2. .0..0..1. .0..0..1. .0..1..2. .0..1..2 %e A273962 ..3..0..0. .0..2..3. .3..1..2. .2..3..0. .2..2..1. .3..0..1. .0..3..3 %e A273962 ..3..2..3. .2..1..1. .1..0..2. .2..1..3. .1..3..2. .3..2..3. .0..2..1 %e A273962 ..2..1..0. .2..3..3. .2..3..0. .0..2..1. .0..0..2. .3..1..2. .3..0..2 %Y A273962 Cf. A273964. %K A273962 nonn %O A273962 1,1 %A A273962 _R. H. Hardin_, Jun 05 2016