A177253 - cp's OEIS frontend

A177253 Number of permutations of [n] having no adjacent 4-cycles, i.e., no cycles of the form (i, i+1, i+2, i+3).

n	a(n)
0	1
1	1
2	2
3	6
4	23
5	118
6	714
7	5016
8	40201
9	362163
10	3623772
11	39876540
12	478639079
13	6223394516
14	87138394540
15	1307195547720
16	20916564680761
17	355600269756485
18	6401066270800350
19	121624180731849810
20	2432546364331038479
21	51084540451761077514
22	1123879093137556106358

[1, 1, 2, 6, 23, 118, 714, 5016, 40201, 362163, 3623772, 39876540, 478639079, 6223394516, 87138394540, 1307195547720, 20916564680761, 355600269756485, 6401066270800350, 121624180731849810, 2432546364331038479, 51084540451761077514, 1123879093137556106358]

cp's OEIS Frontend

A177253 Number of permutations of [n] having no adjacent 4-cycles, i.e., no cycles of the form (i, i+1, i+2, i+3).

Table of values

List of values