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A307588 as a simple table
| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 31 |
| 4 | 999 |
| 5 | 1000 |
| 6 | 31622 |
| 7 | 999999 |
| 8 | 1000000 |
| 9 | 31622776 |
| 10 | 999999999 |
| 11 | 1000000000 |
| 12 | 31622776601 |
| 13 | 999999999999 |
| 14 | 1000000000000 |
| 15 | 31622776601683 |
| 16 | 999999999999999 |
| 17 | 1000000000000000 |
| 18 | 31622776601683792 |
| 19 | 31622776601683793 |
| 20 | 999999999999999999 |
| 21 | 1000000000000000000 |
[0,1,31,999,1000,31622,999999,1000000,31622776, 999999999,1000000000,31622776601,999999999999, 1000000000000,31622776601683,999999999999999, 1000000000000000,31622776601683792, 31622776601683793,999999999999999999, 1000000000000000000] |