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A023812
as a simple table
n
a(n)
1
0
2
2
3
21
4
228
5
2930
6
44790
7
800667
8
16434824
9
381367044
10
9876543210
[0,2,21,228,2930,44790,800667,16434824,381367044, 9876543210]