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| n | a(n) |
|---|---|
| 9 | 1 |
| 10 | 4 |
| 11 | 16 |
| 12 | 65 |
| 13 | 263 |
| 14 | 1077 |
| 15 | 4419 |
| 16 | 18132 |
| 17 | 74368 |
| 18 | 304778 |
| 19 | 1247972 |
| 20 | 5105477 |
| 21 | 20867862 |
| 22 | 85219608 |
| 23 | 347724794 |
| 24 | 1417697157 |
| 25 | 5775652743 |
| 26 | 23512922998 |
| 27 | 95657223246 |
| 28 | 388912046916 |
| 29 | 1580241458120 |
| 30 | 6417249216667 |
| 31 | 26046042351889 |
| 32 | 105661066012240 |
| 33 | 428430870576913 |
[1,4,16,65,263,1077,4419,18132,74368,304778, 1247972,5105477,20867862,85219608,347724794, 1417697157,5775652743,23512922998,95657223246, 388912046916,1580241458120,6417249216667, 26046042351889,105661066012240,428430870576913] |