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A309903 as a simple table

na(n)
00
11
221
371
4196
52071
62071
733321
8345821
9736446
108548946
1118314571
1218314571
13994877071
14994877071
1525408939571
1686444095821
17239031986446
181001971439571
1916260760502071
2092554705814571
21283289569095821
221236963885502071
238389521258548946

[0,1,21,71,196,2071,2071,33321,345821,736446,
 8548946,18314571,18314571,994877071,994877071,
 25408939571,86444095821,239031986446,
 1001971439571,16260760502071,92554705814571,
 283289569095821,1236963885502071,8389521258548946]