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| n | a(n) |
|---|---|
| 1 | 8 |
| 2 | 48 |
| 3 | 204 |
| 4 | 770 |
| 5 | 2687 |
| 6 | 8559 |
| 7 | 25383 |
| 8 | 71498 |
| 9 | 193691 |
| 10 | 508996 |
| 11 | 1306369 |
| 12 | 3291584 |
| 13 | 8173381 |
| 14 | 20060419 |
| 15 | 48777993 |
| 16 | 117717414 |
| 17 | 282365804 |
| 18 | 673959638 |
| 19 | 1602152316 |
| 20 | 3796140809 |
| 21 | 8970338435 |
| 22 | 21150183227 |
| 23 | 49777148466 |
| 24 | 116976012851 |
| 25 | 274555052038 |
[8,48,204,770,2687,8559,25383,71498,193691,508996, 1306369,3291584,8173381,20060419,48777993, 117717414,282365804,673959638,1602152316, 3796140809,8970338435,21150183227,49777148466, 116976012851,274555052038] |