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A002745 as a simple table

na(n)
11
25
320
496
5469
63145
720684
8173544
91557105
1016215253
11159346604
122230085528
1326985045333
14368730610729
155628888393652
1697987283458928
171475486672174337
1829097611462122437
19505383110562327268
2010970329921706735216

[1,5,20,96,469,3145,20684,173544,1557105,16215253,
 159346604,2230085528,26985045333,368730610729,
 5628888393652,97987283458928,1475486672174337,
 29097611462122437,505383110562327268,
 10970329921706735216]