A274873 - cp's OEIS frontend

A274873 Number of set partitions of [n] into exactly nine blocks such that all odd elements are in blocks with an odd index and all even elements are in blocks with an even index.

n	a(n)
9	1
10	4
11	70
12	280
13	2919
14	11676
15	94944
16	379776
17	2669361
18	10677444
19	68321994
20	273287976
21	1640345707
22	6561382828
23	37643205652
24	150572822608
25	836008721925
26	3344034887700
27	18122573826942
28	72490295307768
29	385781480224959
30	1543125920899836
31	8099850233307144

[1, 4, 70, 280, 2919, 11676, 94944, 379776, 2669361, 10677444, 68321994, 273287976, 1640345707, 6561382828, 37643205652, 150572822608, 836008721925, 3344034887700, 18122573826942, 72490295307768, 385781480224959, 1543125920899836, 8099850233307144]

cp's OEIS Frontend

A274873 Number of set partitions of [n] into exactly nine blocks such that all odd elements are in blocks with an odd index and all even elements are in blocks with an even index.

Table of values

List of values