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A216643
as a simple table
n
a(n)
1
1
2
1
3
1
4
1
5
1
6
1
7
1
8
1
9
1
10
1
11
1
12
2
13
4
14
8
15
21
16
45
17
159
18
483
19
1397
20
4252
21
12860
[1,1,1,1,1,1,1,1,1,1,1,2,4,8,21,45,159,483,1397, 4252,12860]