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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 9 |
| 4 | 9 |
| 5 | 30 |
| 6 | 66 |
| 7 | 106 |
| 8 | 274 |
| 9 | 459 |
| 10 | 1010 |
| 11 | 1862 |
| 12 | 3552 |
| 13 | 6973 |
| 14 | 12446 |
| 15 | 24245 |
| 16 | 43041 |
| 17 | 80372 |
| 18 | 144482 |
| 19 | 259633 |
| 20 | 468047 |
| 21 | 822642 |
| 22 | 1468714 |
| 23 | 2556542 |
| 24 | 4493704 |
| 25 | 7782441 |
| 26 | 13470564 |
| 27 | 23204471 |
| 28 | 39679759 |
| 29 | 67855411 |
| 30 | 115004992 |
| 31 | 194984378 |
| 32 | 328183865 |
| 33 | 551595570 |
| 34 | 922663665 |
[1,1,1,9,9,30,66,106,274,459,1010,1862,3552,6973, 12446,24245,43041,80372,144482,259633,468047, 822642,1468714,2556542,4493704,7782441,13470564, 23204471,39679759,67855411,115004992,194984378, 328183865,551595570,922663665] |