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A221729 as a simple table

na(n)
10
216
30
4540
50
622180
70
8911081
90
1037357844
110
121530451369
130
1462678117602
150
162566608259733
170
18105095354454990
190
204303284726664321
210
22176203240002820998
230
247214839389152381265
250
26295419432979789366510
270
2812096265452242634926017

[0,16,0,540,0,22180,0,911081,0,37357844,0,
 1530451369,0,62678117602,0,2566608259733,0,
 105095354454990,0,4303284726664321,0,
 176203240002820998,0,7214839389152381265,0,
 295419432979789366510,0,12096265452242634926017]