A284991 - cp's OEIS frontend

A284991 Triangle T(n,t) read by rows: the number of n X n {0,1} matrices with trace t where each row sum and each column sum is 4.

n	a(n)
0	1
1	0
2	0
3	0
4	0
5	0
6	0
7	0
8	0
9	0
10	0
11	0
12	0
13	0
14	1
15	1
16	0
17	10
18	20
19	45
20	44
21	265
22	1920
23	6300
24	13720
25	20175
26	18000
27	7570
28	357435
29	2398900
30	7499940
31	14372820
32	18433415
33	15729000
34	8171730
35	1975560
36	749649145
37	4695264000
38	13718863480
39	24545693760
40	29544855480
41	24545693760
42	13718863480
43	4695264000
44	749649145

[1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 10, 20, 45, 44, 265, 1920, 6300, 13720, 20175, 18000, 7570, 357435, 2398900, 7499940, 14372820, 18433415, 15729000, 8171730, 1975560, 749649145, 4695264000, 13718863480, 24545693760, 29544855480, 24545693760, 13718863480, 4695264000, 749649145]

cp's OEIS Frontend

A284991 Triangle T(n,t) read by rows: the number of n X n {0,1} matrices with trace t where each row sum and each column sum is 4.

Table of values

List of values