| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 6 |
| 5 | 9 |
| 6 | 15 |
| 7 | 25 |
| 8 | 39 |
| 9 | 63 |
| 10 | 99 |
| 11 | 158 |
| 12 | 251 |
| 13 | 398 |
| 14 | 630 |
| 15 | 999 |
| 16 | 1584 |
| 17 | 2511 |
| 18 | 3981 |
| 19 | 6309 |
| 20 | 9999 |
| 21 | 15848 |
| 22 | 25118 |
| 23 | 39810 |
| 24 | 63095 |
| 25 | 99999 |
| 26 | 158489 |
| 27 | 251188 |
| 28 | 398107 |
| 29 | 630957 |
| 30 | 999999 |
| 31 | 1584893 |
| 32 | 2511886 |
| 33 | 3981071 |
| 34 | 6309573 |
| 35 | 9999999 |
| 36 | 15848931 |
| 37 | 25118864 |
| 38 | 39810717 |
[1,2,3,6,9,15,25,39,63,99,158,251,398,630,999, 1584,2511,3981,6309,9999,15848,25118,39810,63095, 99999,158489,251188,398107,630957,999999,1584893, 2511886,3981071,6309573,9999999,15848931,25118864, 39810717] |