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A243244 as a simple table

na(n)
10
20
30
41
54
630
7317
85511
9165165
108932499
11870814993
12153082769374
1348887756906623

[0,0,0,1,4,30,317,5511,165165,8932499,870814993,
 153082769374,48887756906623]