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| n | a(n) |
|---|---|
| 9 | 1 |
| 10 | 9 |
| 11 | 89 |
| 12 | 639 |
| 13 | 4655 |
| 14 | 30330 |
| 15 | 198148 |
| 16 | 1233743 |
| 17 | 7694099 |
| 18 | 46938514 |
| 19 | 287070944 |
| 20 | 1738940782 |
| 21 | 10570927022 |
| 22 | 64059763010 |
| 23 | 389873574058 |
| 24 | 2373799261605 |
| 25 | 14522526860316 |
| 26 | 89060416668016 |
| 27 | 548932942208392 |
| 28 | 3395326330414774 |
| 29 | 21109553761623110 |
| 30 | 131785019270029876 |
[1,9,89,639,4655,30330,198148,1233743,7694099, 46938514,287070944,1738940782,10570927022, 64059763010,389873574058,2373799261605, 14522526860316,89060416668016,548932942208392, 3395326330414774,21109553761623110, 131785019270029876] |