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A005856
as a simple table
n
a(n)
8
1
9
1
10
1
11
1
12
1
13
2
14
2
15
3
16
4
17
6
18
9
19
12
20
17
21
21
[1,1,1,1,1,2,2,3,4,6,9,12,17,21]