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A121689 as a simple table

na(n)
01
11
22
35
416
557
6231
71023
84926
925483
10140601
11822422
125074015
1332881868
14223027542
151578435549
1611625317128
1788894615929
18704269188135
195770209550496
2048810504348082
21425650324975153
223821377057170313

[1,1,2,5,16,57,231,1023,4926,25483,140601,822422,
 5074015,32881868,223027542,1578435549,11625317128,
 88894615929,704269188135,5770209550496,
 48810504348082,425650324975153,3821377057170313]