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A331678
as a simple table
n
a(n)
1
1
2
3
3
6
4
18
5
44
6
149
7
450
8
1573
9
5352
10
19283
11
69483
12
257206
[1,3,6,18,44,149,450,1573,5352,19283,69483,257206]