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 A155219 #5 May 19 2020 02:19:54 %S A155219 1,4,10,45,176,1305,10079,117352,1561149,29980210,704867467, %T A155219 22571926686,912535595499,49246939684046,3416075823339525, %U A155219 312263317852780140 %N A155219 Number of ways to place zero or more nonadjacent 0,0 1,0 2,0 polyhexes in any orientation on a planar nXnXn triangular grid. %e A155219 Maximal 13 X 13 X 13 example %e A155219 ...............1 %e A155219 ..............1.0 %e A155219 .............1.0.1 %e A155219 ............0.0.0.1 %e A155219 ...........1.1.1.0.1 %e A155219 ..........0.0.0.0.0.0 %e A155219 .........1.0.1.1.1.0.1 %e A155219 ........1.0.0.0.0.0.1.0 %e A155219 .......1.0.1.1.1.0.1.0.1 %e A155219 ......0.0.0.0.0.0.0.0.0.1 %e A155219 .....1.0.1.1.1.0.1.1.1.0.1 %e A155219 ....1.0.0.0.0.0.0.0.0.0.0.0 %e A155219 ...1.0.1.1.1.0.1.1.1.0.1.1.1 %K A155219 nonn,more,hard %O A155219 2,2 %A A155219 _R. H. Hardin_ Jan 22 2009