A143946 - cp's OEIS frontend

A143946 Triangle read by rows: T(n,k) is the number of permutations of [n] for which the sum of the positions of the left-to-right maxima is k (1 <= k <= n(n+1)/2).

n	a(n)
1	1
2	1
3	0
4	1
5	2
6	0
7	2
8	1
9	0
10	1
11	6
12	0
13	6
14	3
15	2
16	3
17	2
18	1
19	0
20	1
21	24
22	0
23	24
24	12
25	8
26	18
27	8
28	10
29	3
30	6
31	3
32	2
33	1
34	0
35	1
36	120
37	0
38	120
39	60
40	40
41	90
42	64
43	50
44	39
45	42
46	23
47	28
48	13
49	10
50	8
51	6
52	3
53	2
54	1
55	0
56	1
57	720
58	0
59	720
60	360
61	240
62	540
63	384
64	420
65	234
66	372
67	198
68	208
69	168
70	124
71	98
72	75
73	60
74	35
75	34
76	13
77	16
78	8
79	6
80	3

[1, 1, 0, 1, 2, 0, 2, 1, 0, 1, 6, 0, 6, 3, 2, 3, 2, 1, 0, 1, 24, 0, 24, 12, 8, 18, 8, 10, 3, 6, 3, 2, 1, 0, 1, 120, 0, 120, 60, 40, 90, 64, 50, 39, 42, 23, 28, 13, 10, 8, 6, 3, 2, 1, 0, 1, 720, 0, 720, 360, 240, 540, 384, 420, 234, 372, 198, 208, 168, 124, 98, 75, 60, 35, 34, 13, 16, 8, 6, 3]

cp's OEIS Frontend

A143946 Triangle read by rows: T(n,k) is the number of permutations of [n] for which the sum of the positions of the left-to-right maxima is k (1 <= k <= n(n+1)/2).

Table of values

List of values

n	a(n)
1	1
2	1
3	0
4	1
5	2
6	0
7	2
8	1
9	0
10	1
11	6
12	0
13	6
14	3
15	2
16	3
17	2
18	1
19	0
20	1
21	24
22	0
23	24
24	12
25	8
26	18
27	8
28	10
29	3
30	6
31	3
32	2
33	1
34	0
35	1
36	120
37	0
38	120
39	60
40	40
41	90
42	64
43	50
44	39
45	42
46	23
47	28
48	13
49	10
50	8
51	6
52	3
53	2
54	1
55	0
56	1
57	720
58	0
59	720
60	360
61	240
62	540
63	384
64	420
65	234
66	372
67	198
68	208
69	168
70	124
71	98
72	75
73	60
74	35
75	34
76	13
77	16
78	8
79	6
80	3

n	a(n)
1	1
2	1
3	0
4	1
5	2
6	0
7	2
8	1
9	0
10	1
11	6
12	0
13	6
14	3
15	2
16	3
17	2
18	1
19	0
20	1
21	24
22	0
23	24
24	12
25	8
26	18
27	8
28	10
29	3
30	6
31	3
32	2
33	1
34	0
35	1
36	120
37	0
38	120
39	60
40	40
41	90
42	64
43	50
44	39
45	42
46	23
47	28
48	13
49	10
50	8
51	6
52	3
53	2
54	1
55	0
56	1
57	720
58	0
59	720
60	360
61	240
62	540
63	384
64	420
65	234
66	372
67	198
68	208
69	168
70	124
71	98
72	75
73	60
74	35
75	34
76	13
77	16
78	8
79	6
80	3

n	a(n)
1	1
2	1
3	0
4	1
5	2
6	0
7	2
8	1
9	0
10	1
11	6
12	0
13	6
14	3
15	2
16	3
17	2
18	1
19	0
20	1
21	24
22	0
23	24
24	12
25	8
26	18
27	8
28	10
29	3
30	6
31	3
32	2
33	1
34	0
35	1
36	120
37	0
38	120
39	60
40	40
41	90
42	64
43	50
44	39
45	42
46	23
47	28
48	13
49	10
50	8
51	6
52	3
53	2
54	1
55	0
56	1
57	720
58	0
59	720
60	360
61	240
62	540
63	384
64	420
65	234
66	372
67	198
68	208
69	168
70	124
71	98
72	75
73	60
74	35
75	34
76	13
77	16
78	8
79	6
80	3