A348455 - cp's OEIS frontend

A348455 Irregular triangle read by rows: T(n,k) (n >= 1, 1 <= k <= number of divisors of n^2) is the number of ways to tile an n X n chessboard with rook-connected polyominoes of area d_k, where d_k is the k-th divisor of n^2.

n	a(n)
1	1
2	1
3	2
4	1
5	1
6	10
7	1
8	1
9	70
10	117
11	36
12	1
13	1
14	4006
15	1
16	1
17	6728
18	80092
19	178939
20	451206
21	442791
22	264500
23	80518
24	1
25	1
26	158753814
27	1

[1, 1, 2, 1, 1, 10, 1, 1, 70, 117, 36, 1, 1, 4006, 1, 1, 6728, 80092, 178939, 451206, 442791, 264500, 80518, 1, 1, 158753814, 1]