A274871 - cp's OEIS frontend

A274871 Number of set partitions of [n] into exactly seven 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)
7	1
8	3
9	34
10	102
11	719
12	2157
13	12260
14	36780
15	185457
16	556371
17	2607078
18	7821234
19	34949443
20	104848329
21	453798280
22	1361394840
23	5763944693
24	17291834079
25	72085646282
26	216256938846
27	891613471047
28	2674840413141
29	10940569830060
30	32821709490180
31	133469376708409

[1, 3, 34, 102, 719, 2157, 12260, 36780, 185457, 556371, 2607078, 7821234, 34949443, 104848329, 453798280, 1361394840, 5763944693, 17291834079, 72085646282, 216256938846, 891613471047, 2674840413141, 10940569830060, 32821709490180, 133469376708409]

cp's OEIS Frontend

A274871 Number of set partitions of [n] into exactly seven 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