A274538 - cp's OEIS frontend

A274538 Number of set partitions of [n] such that each element is contained in a block whose index parity coincides with the parity of the element.

n	a(n)
0	1
1	1
2	1
3	2
4	3
5	7
6	14
7	39
8	95
9	304
10	865
11	3103
12	10038
13	39773
14	143473
15	620382
16	2461099
17	11504723
18	49658054
19	249102263
20	1159930119
21	6205900348
22	30959905841
23	175763987955
24	934068692102
25	5602484594053
26	31563436487785
27	199267671153562
28	1185224170637619

[1, 1, 1, 2, 3, 7, 14, 39, 95, 304, 865, 3103, 10038, 39773, 143473, 620382, 2461099, 11504723, 49658054, 249102263, 1159930119, 6205900348, 30959905841, 175763987955, 934068692102, 5602484594053, 31563436487785, 199267671153562, 1185224170637619]

cp's OEIS Frontend

A274538 Number of set partitions of [n] such that each element is contained in a block whose index parity coincides with the parity of the element.

Table of values

List of values