A166073 - cp's OEIS frontend

A166073 Triangle read by rows: a(n,k) = number of permutations in S_n which avoid the pattern 123 and have exactly k descents.

n	a(n)
0	1
1	1
2	1
3	1
4	0
5	4
6	1
7	0
8	2
9	11
10	1
11	0
12	0
13	15
14	26
15	1
16	0
17	0
18	5
19	69
20	57
21	1
22	0
23	0
24	0
25	56
26	252
27	120
28	1
29	0
30	0
31	0
32	14
33	364
34	804
35	247
36	1
37	0
38	0
39	0
40	0
41	210
42	1800
43	2349
44	502
45	1
46	0
47	0
48	0
49	0
50	42
51	1770
52	7515
53	6455
54	1013
55	1
56	0
57	0
58	0
59	0
60	0
61	792
62	11055
63	27940
64	16962
65	2036
66	1
67	0
68	0
69	0
70	0
71	0
72	132
73	8217
74	57035
75	95458
76	43086
77	4083
78	1

[1, 1, 1, 1, 0, 4, 1, 0, 2, 11, 1, 0, 0, 15, 26, 1, 0, 0, 5, 69, 57, 1, 0, 0, 0, 56, 252, 120, 1, 0, 0, 0, 14, 364, 804, 247, 1, 0, 0, 0, 0, 210, 1800, 2349, 502, 1, 0, 0, 0, 0, 42, 1770, 7515, 6455, 1013, 1, 0, 0, 0, 0, 0, 792, 11055, 27940, 16962, 2036, 1, 0, 0, 0, 0, 0, 132, 8217, 57035, 95458, 43086, 4083, 1]

cp's OEIS Frontend

A166073 Triangle read by rows: a(n,k) = number of permutations in S_n which avoid the pattern 123 and have exactly k descents.

Table of values

List of values