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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 5 |
| 4 | 10 |
| 5 | 26 |
| 6 | 95 |
| 7 | 457 |
| 8 | 2246 |
| 9 | 9705 |
| 10 | 35926 |
| 11 | 115688 |
| 12 | 331201 |
| 13 | 859587 |
| 14 | 2054860 |
| 15 | 4582126 |
| 16 | 9627831 |
| 17 | 19217260 |
| 18 | 36679253 |
| 19 | 67308375 |
| 20 | 119286676 |
| 21 | 204940824 |
| 22 | 342425909 |
| 23 | 557944719 |
| 24 | 888630900 |
| 25 | 1386246251 |
| 26 | 2121866592 |
| 27 | 3191757298 |
[2,3,5,10,26,95,457,2246,9705,35926,115688,331201, 859587,2054860,4582126,9627831,19217260,36679253, 67308375,119286676,204940824,342425909,557944719, 888630900,1386246251,2121866592,3191757298] |