A180986 - cp's OEIS frontend

A180986 T(n,k) = number of n X k binary matrices with rows in lexicographically nondecreasing order and columns in lexicographically nonincreasing order.

n	a(n)
1	2
2	3
3	3
4	4
5	6
6	4
7	5
8	10
9	10
10	5
11	6
12	15
13	20
14	15
15	6
16	7
17	21
18	35
19	35
20	21
21	7
22	8
23	28
24	56
25	70
26	56
27	28
28	8
29	9
30	36
31	84
32	126
33	126
34	84
35	36
36	9
37	10
38	45
39	120
40	210
41	252
42	210
43	120
44	45
45	10
46	11
47	55
48	165
49	330
50	462
51	462
52	330
53	165
54	55
55	11
56	12
57	66
58	220
59	495
60	792
61	924
62	792
63	495
64	220
65	66
66	12
67	13
68	78
69	286
70	715

[2, 3, 3, 4, 6, 4, 5, 10, 10, 5, 6, 15, 20, 15, 6, 7, 21, 35, 35, 21, 7, 8, 28, 56, 70, 56, 28, 8, 9, 36, 84, 126, 126, 84, 36, 9, 10, 45, 120, 210, 252, 210, 120, 45, 10, 11, 55, 165, 330, 462, 462, 330, 165, 55, 11, 12, 66, 220, 495, 792, 924, 792, 495, 220, 66, 12, 13, 78, 286, 715]

cp's OEIS Frontend

A180986 T(n,k) = number of n X k binary matrices with rows in lexicographically nondecreasing order and columns in lexicographically nonincreasing order.

Table of values

List of values

n	a(n)
1	2
2	3
3	3
4	4
5	6
6	4
7	5
8	10
9	10
10	5
11	6
12	15
13	20
14	15
15	6
16	7
17	21
18	35
19	35
20	21
21	7
22	8
23	28
24	56
25	70
26	56
27	28
28	8
29	9
30	36
31	84
32	126
33	126
34	84
35	36
36	9
37	10
38	45
39	120
40	210
41	252
42	210
43	120
44	45
45	10
46	11
47	55
48	165
49	330
50	462
51	462
52	330
53	165
54	55
55	11
56	12
57	66
58	220
59	495
60	792
61	924
62	792
63	495
64	220
65	66
66	12
67	13
68	78
69	286
70	715

n	a(n)
1	2
2	3
3	3
4	4
5	6
6	4
7	5
8	10
9	10
10	5
11	6
12	15
13	20
14	15
15	6
16	7
17	21
18	35
19	35
20	21
21	7
22	8
23	28
24	56
25	70
26	56
27	28
28	8
29	9
30	36
31	84
32	126
33	126
34	84
35	36
36	9
37	10
38	45
39	120
40	210
41	252
42	210
43	120
44	45
45	10
46	11
47	55
48	165
49	330
50	462
51	462
52	330
53	165
54	55
55	11
56	12
57	66
58	220
59	495
60	792
61	924
62	792
63	495
64	220
65	66
66	12
67	13
68	78
69	286
70	715

n	a(n)
1	2
2	3
3	3
4	4
5	6
6	4
7	5
8	10
9	10
10	5
11	6
12	15
13	20
14	15
15	6
16	7
17	21
18	35
19	35
20	21
21	7
22	8
23	28
24	56
25	70
26	56
27	28
28	8
29	9
30	36
31	84
32	126
33	126
34	84
35	36
36	9
37	10
38	45
39	120
40	210
41	252
42	210
43	120
44	45
45	10
46	11
47	55
48	165
49	330
50	462
51	462
52	330
53	165
54	55
55	11
56	12
57	66
58	220
59	495
60	792
61	924
62	792
63	495
64	220
65	66
66	12
67	13
68	78
69	286
70	715