A180185 - cp's OEIS frontend

A180185 Triangle read by rows: T(n,k) is the number of permutations of [n] having no 3-sequences and having k successions (0 <= k <= floor(n/2)); a succession of a permutation p is a position i such that p(i +1) - p(i) = 1.

n	a(n)
0	1
1	1
2	1
3	1
4	3
5	2
6	11
7	9
8	1
9	53
10	44
11	9
12	309
13	265
14	66
15	3
16	2119
17	1854
18	530
19	44
20	16687
21	14833
22	4635
23	530
24	11
25	148329
26	133496
27	44499
28	6180
29	265
30	1468457
31	1334961
32	467236
33	74165
34	4635
35	53
36	16019531
37	14684570
38	5339844
39	934472
40	74165
41	1854
42	190899411

[1, 1, 1, 1, 3, 2, 11, 9, 1, 53, 44, 9, 309, 265, 66, 3, 2119, 1854, 530, 44, 16687, 14833, 4635, 530, 11, 148329, 133496, 44499, 6180, 265, 1468457, 1334961, 467236, 74165, 4635, 53, 16019531, 14684570, 5339844, 934472, 74165, 1854, 190899411]

cp's OEIS Frontend

A180185 Triangle read by rows: T(n,k) is the number of permutations of [n] having no 3-sequences and having k successions (0 <= k <= floor(n/2)); a succession of a permutation p is a position i such that p(i +1) - p(i) = 1.

Table of values

List of values