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A222721 as a simple table

na(n)
120
26524
32807505
41928517786
5662075303107
6474459483232672
7159780846921127290
8118321716926292008569

[20,6524,2807505,1928517786,662075303107,
 474459483232672,159780846921127290,
 118321716926292008569]