A232215 - cp's OEIS frontend

A232215 Number of n X n matrices (up to permutation of their rows and columns) with nonnegative integer entries with all row and column sums equal to 3.

n	a(n)
0	1
1	1
2	2
3	5
4	12
5	31
6	103
7	383
8	1731
9	9273
10	57563
11	406465
12	3212131
13	28009976
14	266688867
15	2749264797
16	30480560319
17	361435864747
18	4562860845767
19	61084137737436
20	864206301930764
21	12882343725953858
22	201788397502682460
23	3313420771907580764
24	56910480298885139055

[1, 1, 2, 5, 12, 31, 103, 383, 1731, 9273, 57563, 406465, 3212131, 28009976, 266688867, 2749264797, 30480560319, 361435864747, 4562860845767, 61084137737436, 864206301930764, 12882343725953858, 201788397502682460, 3313420771907580764, 56910480298885139055]

cp's OEIS Frontend

A232215 Number of n X n matrices (up to permutation of their rows and columns) with nonnegative integer entries with all row and column sums equal to 3.

Table of values

List of values