A064280 - cp's OEIS frontend

A064280 Number of nonequivalent solutions to the order n checkerboard problem up to reflection and rotation: place n pieces on an n X n board so there is exactly one piece in each row, column and main diagonal.

n	a(n)
1	1
2	0
3	0
4	1
5	4
6	12
7	86
8	696
9	6150
10	61760
11	673256
12	8137200
13	105074420
14	1479237312
15	22077680616
16	354753059584
17	6007578698408
18	108500041654272
19	2055204828592832
20	41215470268919040
21	863378484993573840
22	19036646809582054400
23	436944006380312366240

[1, 0, 0, 1, 4, 12, 86, 696, 6150, 61760, 673256, 8137200, 105074420, 1479237312, 22077680616, 354753059584, 6007578698408, 108500041654272, 2055204828592832, 41215470268919040, 863378484993573840, 19036646809582054400, 436944006380312366240]

cp's OEIS Frontend

A064280 Number of nonequivalent solutions to the order n checkerboard problem up to reflection and rotation: place n pieces on an n X n board so there is exactly one piece in each row, column and main diagonal.

Table of values

List of values