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A147009
as a simple table
n
a(n)
1
1
2
1
3
1
4
1
5
1
6
1
7
1
8
3
9
6
10
13
11
20
12
35
13
74
14
191
15
479
16
1455
17
4033
18
12735
19
40335
20
153380
21
583871
[1,1,1,1,1,1,1,3,6,13,20,35,74,191,479,1455,4033, 12735,40335,153380,583871]