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A198253 as a simple table

na(n)
11
21
31
42
55
62
75
840
940
105
1115
12485
131675
14485
1515
1651
176528
1881440
1981440
206528
2151
22187
2390641
244059950
2514520192
264059950
2790641
28187
29715
301268648
31203087097
322606019472
332606019472
34203087097
351268648
36715
372795
3817794141
3910164141586

[1,1,1,2,5,2,5,40,40,5,15,485,1675,485,15,51,6528,
 81440,81440,6528,51,187,90641,4059950,14520192,
 4059950,90641,187,715,1268648,203087097,
 2606019472,2606019472,203087097,1268648,715,2795,
 17794141,10164141586]