A209798 - cp's OEIS frontend

A209798 The number of partitions of the set [n] where each element can be colored 1 or 2 avoiding the patterns 1^11^2, 1^12^2, and 1^22^1 in the pattern sense.

n	a(n)
1	2
2	5
3	12
4	33
5	108
6	411
7	1760
8	8287
9	42302
10	231959
11	1357150
12	8427205
13	55288886
14	381798657
15	2765917104
16	20960284309
17	165729739624
18	1364153612335
19	11665484410132
20	103448316470763
21	949739632313522
22	9013431476894667
23	88304011710168714
24	891917738589610601

[2, 5, 12, 33, 108, 411, 1760, 8287, 42302, 231959, 1357150, 8427205, 55288886, 381798657, 2765917104, 20960284309, 165729739624, 1364153612335, 11665484410132, 103448316470763, 949739632313522, 9013431476894667, 88304011710168714, 891917738589610601]

cp's OEIS Frontend

A209798 The number of partitions of the set [n] where each element can be colored 1 or 2 avoiding the patterns 1^11^2, 1^12^2, and 1^22^1 in the pattern sense.

Table of values

List of values