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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 10 |
| 3 | 10 |
| 4 | 20 |
| 5 | 90 |
| 6 | 20 |
| 7 | 35 |
| 8 | 631 |
| 9 | 631 |
| 10 | 35 |
| 11 | 56 |
| 12 | 3567 |
| 13 | 19827 |
| 14 | 3567 |
| 15 | 56 |
| 16 | 83 |
| 17 | 16493 |
| 18 | 499474 |
| 19 | 499474 |
| 20 | 16493 |
| 21 | 83 |
| 22 | 116 |
| 23 | 64018 |
| 24 | 9603489 |
| 25 | 56836178 |
| 26 | 9603489 |
| 27 | 64018 |
| 28 | 116 |
| 29 | 155 |
| 30 | 213013 |
| 31 | 144262866 |
| 32 | 4720850001 |
| 33 | 4720850001 |
| 34 | 144262866 |
| 35 | 213013 |
| 36 | 155 |
| 37 | 200 |
| 38 | 621757 |
[4,10,10,20,90,20,35,631,631,35,56,3567,19827, 3567,56,83,16493,499474,499474,16493,83,116,64018, 9603489,56836178,9603489,64018,116,155,213013, 144262866,4720850001,4720850001,144262866,213013, 155,200,621757] |