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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 3 |
| 3 | 4 |
| 4 | 9 |
| 5 | 30 |
| 6 | 91 |
| 7 | 232 |
| 8 | 549 |
| 9 | 1378 |
| 10 | 3839 |
| 11 | 11100 |
| 12 | 31301 |
| 13 | 85694 |
| 14 | 234207 |
| 15 | 653328 |
| 16 | 1856829 |
| 17 | 5300010 |
| 18 | 15062839 |
| 19 | 42702596 |
| 20 | 121448901 |
| 21 | 347414166 |
| 22 | 997886671 |
| 23 | 2870139480 |
| 24 | 8257776521 |
| 25 | 23782773242 |
| 26 | 68627659563 |
| 27 | 198437633884 |
| 28 | 574654851209 |
| 29 | 1665825647430 |
| 30 | 4833258038251 |
| 31 | 14037680955552 |
| 32 | 40816416373293 |
[1,2,3,4,9,30,91,232,549,1378,3839,11100,31301, 85694,234207,653328,1856829,5300010,15062839, 42702596,121448901,347414166,997886671,2870139480, 8257776521,23782773242,68627659563,198437633884, 574654851209,1665825647430,4833258038251, 14037680955552,40816416373293] |