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A006281
as a simple table
n
a(n)
0
0
1
3
2
2
3
18
4
98
5
33282
6
319994402
7
354455304050635218
8
36294953231792713902640647988908098
[0,3,2,18,98,33282,319994402,354455304050635218, 36294953231792713902640647988908098]