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A004127 as a simple table

na(n)
11
21
33
412
568
6483
73946
834485
9315810
102984570
1128907970
12285601251
132868869733
1429227904840
15301430074416
163141985563575
1733059739636198
18350763452126835
193749420616902637
2040348040718155170
21436827335493148600

[1,1,3,12,68,483,3946,34485,315810,2984570,
 28907970,285601251,2868869733,29227904840,
 301430074416,3141985563575,33059739636198,
 350763452126835,3749420616902637,
 40348040718155170,436827335493148600]