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 A205553 #8 Jul 03 2020 14:55:05 %S A205553 1,1,1,1,2,1,1,4,1,1,1,6,6,3,1,1,8,15,4,6,1,1,10,28,20,1,10,1,1,12,45, %T A205553 56,15,5,15,1,1,14,66,120,70,6,15,21,1,1,16,91,220,210,56,1,35,28,1,1, %U A205553 18,120,364,495,252,28,7,70,36,1,1,20,153,560,1001,792,210,8 %N A205553 Square array by antidiagonals: C(max(i-1,2j-2),min(i-1,2j-2)), i>=1, j>=1. %H A205553 Milan Janjic, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL19/Janjic/janjic73.html">Binomial Coefficients and Enumeration of Restricted Words</a>, Journal of Integer Sequences, 2016, Vol 19, #16.7.3 %e A205553 Northwest corner: %e A205553 1....1....1....1....1 %e A205553 1....2....4....6....8 %e A205553 1....1....6....15...28 %e A205553 1....3....4....20...56 %e A205553 1....6....1....15...70 %t A205553 f[i_, j_] := Binomial[Max[i - 1, 2 j - 2], Min[i - 1, 2 j - 2]] %t A205553 TableForm[Table[f[i, j], {i, 1, 10}, {j, 1, 10}]] %t A205553 Flatten[Table[f[i, n + 1 - i], {n, 1, 14}, {i, 1, n}]] %Y A205553 Cf. A205456. %K A205553 nonn,tabl %O A205553 1,5 %A A205553 _Clark Kimberling_, Jan 28 2012