A184049 - cp's OEIS frontend

A184049 T(n,k) is the number of order-preserving and order-decreasing partial isometries (of an n-chain) of height k (height of alpha = |Im(alpha)|).

n	a(n)
0	1
1	1
2	1
3	1
4	3
5	1
6	1
7	6
8	4
9	1
10	1
11	10
12	10
13	5
14	1
15	1
16	15
17	20
18	15
19	6
20	1
21	1
22	21
23	35
24	35
25	21
26	7
27	1
28	1
29	28
30	56
31	70
32	56
33	28
34	8
35	1
36	1
37	36
38	84
39	126
40	126
41	84
42	36
43	9
44	1
45	1
46	45
47	120
48	210
49	252
50	210
51	120
52	45
53	10
54	1
55	1
56	55
57	165
58	330
59	462
60	462
61	330
62	165
63	55
64	11
65	1
66	1
67	66
68	220

[1, 1, 1, 1, 3, 1, 1, 6, 4, 1, 1, 10, 10, 5, 1, 1, 15, 20, 15, 6, 1, 1, 21, 35, 35, 21, 7, 1, 1, 28, 56, 70, 56, 28, 8, 1, 1, 36, 84, 126, 126, 84, 36, 9, 1, 1, 45, 120, 210, 252, 210, 120, 45, 10, 1, 1, 55, 165, 330, 462, 462, 330, 165, 55, 11, 1, 1, 66, 220]

cp's OEIS Frontend

A184049 T(n,k) is the number of order-preserving and order-decreasing partial isometries (of an n-chain) of height k (height of alpha = |Im(alpha)|).

Table of values

List of values

n	a(n)
0	1
1	1
2	1
3	1
4	3
5	1
6	1
7	6
8	4
9	1
10	1
11	10
12	10
13	5
14	1
15	1
16	15
17	20
18	15
19	6
20	1
21	1
22	21
23	35
24	35
25	21
26	7
27	1
28	1
29	28
30	56
31	70
32	56
33	28
34	8
35	1
36	1
37	36
38	84
39	126
40	126
41	84
42	36
43	9
44	1
45	1
46	45
47	120
48	210
49	252
50	210
51	120
52	45
53	10
54	1
55	1
56	55
57	165
58	330
59	462
60	462
61	330
62	165
63	55
64	11
65	1
66	1
67	66
68	220

n	a(n)
0	1
1	1
2	1
3	1
4	3
5	1
6	1
7	6
8	4
9	1
10	1
11	10
12	10
13	5
14	1
15	1
16	15
17	20
18	15
19	6
20	1
21	1
22	21
23	35
24	35
25	21
26	7
27	1
28	1
29	28
30	56
31	70
32	56
33	28
34	8
35	1
36	1
37	36
38	84
39	126
40	126
41	84
42	36
43	9
44	1
45	1
46	45
47	120
48	210
49	252
50	210
51	120
52	45
53	10
54	1
55	1
56	55
57	165
58	330
59	462
60	462
61	330
62	165
63	55
64	11
65	1
66	1
67	66
68	220

n	a(n)
0	1
1	1
2	1
3	1
4	3
5	1
6	1
7	6
8	4
9	1
10	1
11	10
12	10
13	5
14	1
15	1
16	15
17	20
18	15
19	6
20	1
21	1
22	21
23	35
24	35
25	21
26	7
27	1
28	1
29	28
30	56
31	70
32	56
33	28
34	8
35	1
36	1
37	36
38	84
39	126
40	126
41	84
42	36
43	9
44	1
45	1
46	45
47	120
48	210
49	252
50	210
51	120
52	45
53	10
54	1
55	1
56	55
57	165
58	330
59	462
60	462
61	330
62	165
63	55
64	11
65	1
66	1
67	66
68	220