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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 21 |
| 5 | 1 |
| 6 | 1 |
| 7 | 421 |
| 8 | 421 |
| 9 | 1 |
| 10 | 1 |
| 11 | 8421 |
| 12 | 168821 |
| 13 | 8421 |
| 14 | 1 |
| 15 | 1 |
| 16 | 168421 |
| 17 | 67536821 |
| 18 | 67536821 |
| 19 | 168421 |
| 20 | 1 |
| 21 | 1 |
| 22 | 3368421 |
| 23 | 27014896821 |
| 24 | 540362104821 |
| 25 | 27014896821 |
| 26 | 3368421 |
| 27 | 1 |
| 28 | 1 |
| 29 | 67368421 |
| 30 | 10805962096821 |
| 31 | 4322923853464821 |
[1,1,1,1,21,1,1,421,421,1,1,8421,168821,8421,1,1, 168421,67536821,67536821,168421,1,1,3368421, 27014896821,540362104821,27014896821,3368421,1,1, 67368421,10805962096821,4322923853464821] |