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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 1 |
| 4 | 18 |
| 5 | 9 |
| 6 | 163 |
| 7 | 90 |
| 8 | 3 |
| 9 | 1950 |
| 10 | 1100 |
| 11 | 75 |
| 12 | 28821 |
| 13 | 16245 |
| 14 | 1575 |
| 15 | 15 |
| 16 | 505876 |
| 17 | 283122 |
| 18 | 33810 |
| 19 | 735 |
| 20 | 10270569 |
| 21 | 5699932 |
| 22 | 780150 |
| 23 | 26460 |
| 24 | 105 |
| 25 | 236644092 |
| 26 | 130267440 |
| 27 | 19615932 |
| 28 | 884520 |
| 29 | 8505 |
| 30 | 6098971555 |
| 31 | 3332614725 |
| 32 | 538325550 |
| 33 | 29619450 |
| 34 | 467775 |
| 35 | 945 |
[1,1,3,1,18,9,163,90,3,1950,1100,75,28821,16245, 1575,15,505876,283122,33810,735,10270569,5699932, 780150,26460,105,236644092,130267440,19615932, 884520,8505,6098971555,3332614725,538325550, 29619450,467775,945] |