A228917 - OEIS

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A228917 as a simple table

n	a(n)
1	1
2	1
3	1
4	2
5	2
6	2
7	5
8	2
9	12
10	39
11	98
12	526
13	2117
14	6663
15	15043
16	68403
17	791581
18	4826577
19	19592777
20	102551299
21	739788968
22	4449585790
23	36547266589
24	324446266072
25	2743681178070

[1,1,1,2,2,2,5,2,12,39,98,526,2117,6663,15043, 68403,791581,4826577,19592777,102551299,739788968, 4449585790,36547266589,324446266072,2743681178070]