A287668 - cp's OEIS frontend

A287668 Number of set partitions of [n] such that j is member of block b only if b = 1 or at least one of j-1, ..., j-5 is member of a block >= b-1.

n	a(n)
0	1
1	1
2	2
3	5
4	15
5	52
6	203
7	877
8	4139
9	21107
10	115301
11	670059
12	4119316
13	26665103
14	181031235
15	1284643851
16	9500643629
17	73037739470
18	582346938182
19	4805997066022
20	40980051074202
21	360452146946076
22	3265691382361850
23	30435437254066599
24	291431082211368120

[1, 1, 2, 5, 15, 52, 203, 877, 4139, 21107, 115301, 670059, 4119316, 26665103, 181031235, 1284643851, 9500643629, 73037739470, 582346938182, 4805997066022, 40980051074202, 360452146946076, 3265691382361850, 30435437254066599, 291431082211368120]

cp's OEIS Frontend

A287668 Number of set partitions of [n] such that j is member of block b only if b = 1 or at least one of j-1, ..., j-5 is member of a block >= b-1.

Table of values

List of values