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 A049702 #8 Apr 20 2013 03:05:23
%S A049702 0,1,1,1,4,1,1,6,6,1,1,8,8,8,1,1,10,12,12,10,1,1,12,14,16,14,12,1,1,
%T A049702 14,18,20,20,18,14,1,1,16,20,26,24,26,20,16,1,1,18,24,28,32,32,28,24,
%U A049702 18,1,1,20,26,34,34,40,34,34,26,20,1,1,22,30,38
%N A049702 Array T read by diagonals; T(i,j)=number of directions determined by 2 lattice points in [ 0,i ]x[ 0,j ].
%e A049702 Diagonals (each starting on row 1): {0}; {1,1}; {1,4,1}; ...
%K A049702 nonn,tabl
%O A049702 0,5
%A A049702 _Clark Kimberling_