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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 3 |
| 3 | 8 |
| 4 | 18 |
| 5 | 42 |
| 6 | 97 |
| 7 | 225 |
| 8 | 521 |
| 9 | 1207 |
| 10 | 2796 |
| 11 | 6477 |
| 12 | 15004 |
| 13 | 34757 |
| 14 | 80515 |
| 15 | 186514 |
| 16 | 432062 |
| 17 | 1000877 |
| 18 | 2318544 |
| 19 | 5370936 |
| 20 | 12441840 |
| 21 | 28821677 |
| 22 | 66765773 |
| 23 | 154663743 |
| 24 | 358280483 |
| 25 | 829961192 |
| 26 | 1922615417 |
| 27 | 4453762510 |
| 28 | 10317196211 |
| 29 | 23899913257 |
| 30 | 55364446116 |
| 31 | 128252427562 |
| 32 | 297098342519 |
| 33 | 688232003132 |
[1,2,3,8,18,42,97,225,521,1207,2796,6477,15004, 34757,80515,186514,432062,1000877,2318544,5370936, 12441840,28821677,66765773,154663743,358280483, 829961192,1922615417,4453762510,10317196211, 23899913257,55364446116,128252427562,297098342519, 688232003132] |