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A049891 as a simple table

na(n)
11
21
32
43
54
610
718
829
939
10106
11210
12413
13807
141537
152767
164410
175947
1816303
1932604
2065201
21130383
22260689
23521071
241041018
252079163
264146433
278243968
2816292448
2931804567
3060503719
31108861423
32173511575
33234015294
34641542162

[1,1,2,3,4,10,18,29,39,106,210,413,807,1537,2767,
 4410,5947,16303,32604,65201,130383,260689,521071,
 1041018,2079163,4146433,8243968,16292448,31804567,
 60503719,108861423,173511575,234015294,641542162]