A216121 - cp's OEIS frontend

A216121 Irregular triangle read by rows: T(n,k) is the number of permutations in C_n (= the 1-cycles in S_n) having k stretching pairs.

n	a(n)
1	1
2	1
3	2
4	5
5	1
6	16
7	6
8	2
9	63
10	31
11	20
12	5
13	1
14	294
15	168
16	150
17	70
18	30
19	6
20	2
21	1585
22	997
23	1072
24	691
25	423
26	171
27	75
28	20
29	5
30	1
31	9692
32	6522
33	7882
34	6176
35	4744
36	2612
37	1598
38	656
39	300
40	100
41	30
42	6
43	2
44	66275
45	46891
46	61356
47	54561
48	49013
49	32689
50	24285
51	13429
52	7812
53	3795
54	1759
55	651
56	263
57	75
58	20
59	5
60	1

[1, 1, 2, 5, 1, 16, 6, 2, 63, 31, 20, 5, 1, 294, 168, 150, 70, 30, 6, 2, 1585, 997, 1072, 691, 423, 171, 75, 20, 5, 1, 9692, 6522, 7882, 6176, 4744, 2612, 1598, 656, 300, 100, 30, 6, 2, 66275, 46891, 61356, 54561, 49013, 32689, 24285, 13429, 7812, 3795, 1759, 651, 263, 75, 20, 5, 1]

cp's OEIS Frontend

A216121 Irregular triangle read by rows: T(n,k) is the number of permutations in C_n (= the 1-cycles in S_n) having k stretching pairs.

Table of values

List of values