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A070521 as a simple table

na(n)
12
27
3121
45461
512207031
62612138803
738771752331201
820587884010836553
91107867264956562636991
1011111111111111111111111111111
1119194342495775048050414684129181
12773238409074645649506921062192257266781
13391287702091575733090747617444785169589677401

[2,7,121,5461,12207031,2612138803,38771752331201,
 20587884010836553,1107867264956562636991,
 11111111111111111111111111111,
 19194342495775048050414684129181,
 773238409074645649506921062192257266781,
 391287702091575733090747617444785169589677401]