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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 7 |
| 3 | 15 |
| 4 | 32 |
| 5 | 72 |
| 6 | 178 |
| 7 | 494 |
| 8 | 1543 |
| 9 | 5373 |
| 10 | 20581 |
| 11 | 85653 |
| 12 | 383494 |
| 13 | 1833250 |
| 14 | 9301792 |
| 15 | 49857540 |
| 16 | 281193501 |
| 17 | 1663183383 |
| 18 | 10286884195 |
| 19 | 66365330811 |
| 20 | 445598473612 |
| 21 | 3107611606908 |
| 22 | 22470529228910 |
| 23 | 168190079241210 |
| 24 | 1301213084182483 |
| 25 | 10391369994732593 |
| 26 | 85553299734530113 |
[1,3,7,15,32,72,178,494,1543,5373,20581,85653, 383494,1833250,9301792,49857540,281193501, 1663183383,10286884195,66365330811,445598473612, 3107611606908,22470529228910,168190079241210, 1301213084182483,10391369994732593, 85553299734530113] |