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| n | a(n) |
|---|---|
| 0 | 3 |
| 1 | 19 |
| 2 | 99 |
| 3 | 499 |
| 4 | 2499 |
| 5 | 12499 |
| 6 | 62499 |
| 7 | 312499 |
| 8 | 1562499 |
| 9 | 7812499 |
| 10 | 39062499 |
| 11 | 195312499 |
| 12 | 976562499 |
| 13 | 4882812499 |
| 14 | 24414062499 |
| 15 | 122070312499 |
| 16 | 610351562499 |
| 17 | 3051757812499 |
| 18 | 15258789062499 |
| 19 | 76293945312499 |
| 20 | 381469726562499 |
| 21 | 1907348632812499 |
[3,19,99,499,2499,12499,62499,312499,1562499, 7812499,39062499,195312499,976562499,4882812499, 24414062499,122070312499,610351562499, 3051757812499,15258789062499,76293945312499, 381469726562499,1907348632812499] |