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A064670 as a simple table

na(n)
11
21
34
45
520
636
761
8244
9504
10576
111385
125540
1311916
1417280
1514400
1650521
17202084
18442224
19697536
20792000
21518400
222702765
2310811060
2423870196
2539202560
2650198400
2747174400
2825401600
29199360981
30797443924
311769923944

[1,1,4,5,20,36,61,244,504,576,1385,5540,11916,
 17280,14400,50521,202084,442224,697536,792000,
 518400,2702765,10811060,23870196,39202560,
 50198400,47174400,25401600,199360981,797443924,
 1769923944]