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 A059217 #12 Dec 30 2016 06:10:12
%S A059217 1,1,2,5,3,1,1,6,10,14,45,37,26,15,1,1,46,84,121,150,169,740,686,592,
%T A059217 471,321,170,1,1,741,1428,2111,2704,3183,3532,3721,21142,20347,18826,
%U A059217 16685,13953,10777,7255,3722,1,1,21143,41491,61798,80598
%N A059217 The array in A059216 read by antidiagonals in 'up' direction.
%H A059217 G. C. Greubel, <a href="/A059217/b059217.txt">Table of n, a(n) for the first 50 rows, flattened</a>
%e A059217 The array begins
%e A059217 1 2 1 14 1 ...
%e A059217 1 3 10 15 ...
%e A059217 5 6 26 ...
%e A059217 1 37 ...
%e A059217 45 ...
%p A059217 See A059216 for Maple code.
%t A059217 max = 9; t[0, 0] = 1; t[0, _?EvenQ] = 1; t[_?OddQ, 0] = 1; t[n_, k_] /; OddQ[n + k](*up*):= t[n, k] = t[n+1, k-1] + Sum[t[n, j], {j, 0, k-1}]; t[n_, k_] /; EvenQ[n + k](*down*):= t[n, k] = t[n-1, k+1] + Sum[t[j, k], {j, 0, n-1}]; Table[t[n-k, k], {n, 0, max}, {k, 0, n}] // Flatten (* _Jean-François Alcover_, Sep 16 2013 *)
%Y A059217 Cf. A000667, A059216, A059219, A059220, A059234.
%K A059217 easy,nonn,tabl,nice
%O A059217 1,3
%A A059217 _Floor van Lamoen_, Jan 18 2001