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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 4 |
| 7 | 1 |
| 8 | 1 |
| 9 | 4 |
| 10 | 20 |
| 11 | 1 |
| 12 | 1 |
| 13 | 4 |
| 14 | 20 |
| 15 | 520 |
| 16 | 1 |
| 17 | 1 |
| 18 | 4 |
| 19 | 20 |
| 20 | 520 |
| 21 | 26440 |
| 22 | 1 |
| 23 | 1 |
| 24 | 4 |
| 25 | 20 |
| 26 | 520 |
| 27 | 26440 |
| 28 | 8766080 |
| 29 | 1 |
| 30 | 1 |
| 31 | 4 |
| 32 | 20 |
| 33 | 520 |
| 34 | 26440 |
| 35 | 8766080 |
| 36 | 6939853440 |
| 37 | 1 |
| 38 | 1 |
| 39 | 4 |
| 40 | 20 |
| 41 | 520 |
| 42 | 26440 |
| 43 | 8766080 |
| 44 | 6939853440 |
| 45 | 41934828744960 |
| 46 | 1 |
| 47 | 1 |
| 48 | 4 |
| 49 | 20 |
| 50 | 520 |
| 51 | 26440 |
| 52 | 8766080 |
| 53 | 6939853440 |
| 54 | 41934828744960 |
| 55 | 694027278828744960 |
[1,1,1,1,1,4,1,1,4,20,1,1,4,20,520,1,1,4,20,520, 26440,1,1,4,20,520,26440,8766080,1,1,4,20,520, 26440,8766080,6939853440,1,1,4,20,520,26440, 8766080,6939853440,41934828744960,1,1,4,20,520, 26440,8766080,6939853440,41934828744960, 694027278828744960] |