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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 8 |
| 5 | 16 |
| 6 | 31 |
| 7 | 60 |
| 8 | 114 |
| 9 | 215 |
| 10 | 402 |
| 11 | 7464 |
| 12 | 1375 |
| 13 | 2520 |
| 14 | 4593 |
| 15 | 8329 |
| 16 | 15036 |
| 17 | 27027 |
| 18 | 48389 |
| 19 | 86314 |
| 20 | 153432 |
[1,1,2,4,8,16,31,60,114,215,402,7464,1375,2520, 4593,8329,15036,27027,48389,86314,153432] |