A221057 - cp's OEIS frontend

A221057 Irregular triangle read by rows: T(n,k) is the number of Dyck prefixes of length n having k inversions (n >= 0, k >= 0).

n	a(n)
0	1
1	1
2	2
3	2
4	1
5	3
6	2
7	1
8	3
9	2
10	3
11	2
12	4
13	3
14	5
15	4
16	3
17	1
18	4
19	3
20	5
21	6
22	7
23	6
24	3
25	1
26	5
27	4
28	7
29	9
30	11
31	11
32	10
33	6
34	5
35	2
36	5
37	4
38	7
39	9
40	13
41	14
42	18
43	17
44	15
45	12
46	7
47	4
48	1
49	6
50	5
51	9
52	12
53	18
54	20
55	27
56	28
57	30
58	26
59	23
60	19
61	15
62	9
63	4
64	1
65	6
66	5
67	9
68	12
69	18
70	22
71	30
72	34
73	42
74	45
75	46
76	46
77	44
78	36
79	28
80	19
81	11
82	7
83	2
84	7
85	6
86	11
87	15
88	23
89	29
90	40
91	47
92	60
93	68
94	76
95	78
96	82
97	77
98	73
99	63
100	56
101	44
102	32
103	20
104	11
105	5
106	1

[1, 1, 2, 2, 1, 3, 2, 1, 3, 2, 3, 2, 4, 3, 5, 4, 3, 1, 4, 3, 5, 6, 7, 6, 3, 1, 5, 4, 7, 9, 11, 11, 10, 6, 5, 2, 5, 4, 7, 9, 13, 14, 18, 17, 15, 12, 7, 4, 1, 6, 5, 9, 12, 18, 20, 27, 28, 30, 26, 23, 19, 15, 9, 4, 1, 6, 5, 9, 12, 18, 22, 30, 34, 42, 45, 46, 46, 44, 36, 28, 19, 11, 7, 2, 7, 6, 11, 15, 23, 29, 40, 47, 60, 68, 76, 78, 82, 77, 73, 63, 56, 44, 32, 20, 11, 5, 1]

cp's OEIS Frontend

A221057 Irregular triangle read by rows: T(n,k) is the number of Dyck prefixes of length n having k inversions (n >= 0, k >= 0).

Table of values

List of values

n	a(n)
0	1
1	1
2	2
3	2
4	1
5	3
6	2
7	1
8	3
9	2
10	3
11	2
12	4
13	3
14	5
15	4
16	3
17	1
18	4
19	3
20	5
21	6
22	7
23	6
24	3
25	1
26	5
27	4
28	7
29	9
30	11
31	11
32	10
33	6
34	5
35	2
36	5
37	4
38	7
39	9
40	13
41	14
42	18
43	17
44	15
45	12
46	7
47	4
48	1
49	6
50	5
51	9
52	12
53	18
54	20
55	27
56	28
57	30
58	26
59	23
60	19
61	15
62	9
63	4
64	1
65	6
66	5
67	9
68	12
69	18
70	22
71	30
72	34
73	42
74	45
75	46
76	46
77	44
78	36
79	28
80	19
81	11
82	7
83	2
84	7
85	6
86	11
87	15
88	23
89	29
90	40
91	47
92	60
93	68
94	76
95	78
96	82
97	77
98	73
99	63
100	56
101	44
102	32
103	20
104	11
105	5
106	1

n	a(n)
0	1
1	1
2	2
3	2
4	1
5	3
6	2
7	1
8	3
9	2
10	3
11	2
12	4
13	3
14	5
15	4
16	3
17	1
18	4
19	3
20	5
21	6
22	7
23	6
24	3
25	1
26	5
27	4
28	7
29	9
30	11
31	11
32	10
33	6
34	5
35	2
36	5
37	4
38	7
39	9
40	13
41	14
42	18
43	17
44	15
45	12
46	7
47	4
48	1
49	6
50	5
51	9
52	12
53	18
54	20
55	27
56	28
57	30
58	26
59	23
60	19
61	15
62	9
63	4
64	1
65	6
66	5
67	9
68	12
69	18
70	22
71	30
72	34
73	42
74	45
75	46
76	46
77	44
78	36
79	28
80	19
81	11
82	7
83	2
84	7
85	6
86	11
87	15
88	23
89	29
90	40
91	47
92	60
93	68
94	76
95	78
96	82
97	77
98	73
99	63
100	56
101	44
102	32
103	20
104	11
105	5
106	1

n	a(n)
0	1
1	1
2	2
3	2
4	1
5	3
6	2
7	1
8	3
9	2
10	3
11	2
12	4
13	3
14	5
15	4
16	3
17	1
18	4
19	3
20	5
21	6
22	7
23	6
24	3
25	1
26	5
27	4
28	7
29	9
30	11
31	11
32	10
33	6
34	5
35	2
36	5
37	4
38	7
39	9
40	13
41	14
42	18
43	17
44	15
45	12
46	7
47	4
48	1
49	6
50	5
51	9
52	12
53	18
54	20
55	27
56	28
57	30
58	26
59	23
60	19
61	15
62	9
63	4
64	1
65	6
66	5
67	9
68	12
69	18
70	22
71	30
72	34
73	42
74	45
75	46
76	46
77	44
78	36
79	28
80	19
81	11
82	7
83	2
84	7
85	6
86	11
87	15
88	23
89	29
90	40
91	47
92	60
93	68
94	76
95	78
96	82
97	77
98	73
99	63
100	56
101	44
102	32
103	20
104	11
105	5
106	1