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 A063179 #8 Apr 21 2023 17:14:27 %S A063179 1,1,2,4,12,42,178,870,4830,29976,205572,1543210,12583242,110725638, %T A063179 1045664646,10547679660,113172039256,1286925785286,15459448549274, %U A063179 195616259182162,2600506074185090,36235386548738016,528084808585261568,8033872923106040478 %N A063179 Di-Boustrophedon transform of (1,0,0,0,...): Fill in an array by diagonals alternating in the 'up' and 'down' directions. The n-th diagonal starts with the n-th element of (1,0,0,0,...). When going in the 'up' direction the next element is the sum of the previous element of the diagonal and the previous two elements of the row the new element is in. When going in the 'down' direction the next element is the sum of the previous element of the diagonal and the previous two elements of the column the new element is in. The final element of the n-th diagonal is a(n). %e A063179 Array begins: %e A063179 1 1 0 4 0 42 ... %e A063179 0 1 3 4 38 ... %e A063179 2 2 7 31 ... %e A063179 0 10 22 ... %e A063179 12 12 ... %e A063179 0 ... %Y A063179 Cf. A000667, A059216, A062704, A063180, A063181. %K A063179 easy,nonn %O A063179 1,3 %A A063179 _Floor van Lamoen_, Jul 09 2001 %E A063179 More terms from _Sean A. Irvine_, Apr 21 2023