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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 9 |
| 5 | 20 |
| 6 | 45 |
| 7 | 102 |
| 8 | 231 |
| 9 | 524 |
| 10 | 1189 |
| 11 | 2698 |
| 12 | 6124 |
| 13 | 13900 |
| 14 | 31551 |
| 15 | 71618 |
| 16 | 162566 |
| 17 | 369013 |
| 18 | 837633 |
| 19 | 1901368 |
| 20 | 4315978 |
| 21 | 9796979 |
| 22 | 22238489 |
| 23 | 50479892 |
| 24 | 114585999 |
| 25 | 260102617 |
| 26 | 590415686 |
| 27 | 1340204451 |
| 28 | 3042175244 |
| 29 | 6905536091 |
| 30 | 15675109089 |
| 31 | 35581458383 |
| 32 | 80767551510 |
[1,1,2,4,9,20,45,102,231,524,1189,2698,6124,13900, 31551,71618,162566,369013,837633,1901368,4315978, 9796979,22238489,50479892,114585999,260102617, 590415686,1340204451,3042175244,6905536091, 15675109089,35581458383,80767551510] |