数组A(n,k)的开头是:
0, 1, 0, 3, 0, 9, 0, 27, ...请参见A000244号;
4, 7, 12, 21, 36, 63, 108, 189, ...A228879型;
15, 26, 45, 78, 135, 234, 405, 702, ...
56, 97, 168, 291, 504, 873, 1512, 2619, ...
209, 362, 627, 1086, 1881, 3258, 5643, 9774, ...
780, 1351, 2340, 4053, 7020, 12159, 21060, 36477, ...
反对角三角形T(n,k)的开头为:
0;
1, 1;
0, 2, 4;
3, 3, 7, 15;
0, 6, 12, 26, 56;
9, 9, 21, 45, 97, 209;
0, 18, 36, 78, 168, 362, 780;
27, 27, 63, 135, 291, 627, 1351, 2911;
0, 54, 108, 234, 504, 1086, 2340, 5042, 10864;
81, 81, 189, 405, 873, 1881, 4053, 8733, 18817, 40545;