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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 4 |
| 3 | 22 |
| 4 | 64 |
| 5 | 132 |
| 6 | 231 |
| 7 | 5472 |
| 8 | 8877 |
| 9 | 34635 |
| 10 | 57550 |
| 11 | 75542 |
| 12 | 636667 |
| 13 | 739799 |
| 14 | 1291879 |
| 15 | 2081880 |
| 16 | 3064827 |
| 17 | 4039368 |
| 18 | 9433189 |
| 19 | 16966370 |
| 20 | 211947608 |
| 21 | 367298045 |
| 22 | 1101086463 |
| 23 | 1541079585 |
| 24 | 16915330550 |
| 25 | 20775909209 |
| 26 | 24450416187 |
| 27 | 575276374739 |
| 28 | 707965641746 |
| 29 | 3731987263894 |
[2,4,22,64,132,231,5472,8877,34635,57550,75542, 636667,739799,1291879,2081880,3064827,4039368, 9433189,16966370,211947608,367298045,1101086463, 1541079585,16915330550,20775909209,24450416187, 575276374739,707965641746,3731987263894] |