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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 23 |
| 3 | 83 |
| 4 | 89 |
| 5 | 287 |
| 6 | 689 |
| 7 | 1723 |
| 8 | 4491 |
| 9 | 10433 |
| 10 | 28009 |
| 11 | 73289 |
| 12 | 182043 |
| 13 | 464679 |
| 14 | 1196593 |
| 15 | 3100505 |
| 16 | 7907085 |
| 17 | 20156111 |
| 18 | 51965647 |
| 19 | 133805425 |
| 20 | 342839837 |
| 21 | 878417801 |
| 22 | 2258261501 |
| 23 | 5808644113 |
| 24 | 14907781647 |
| 25 | 38258830449 |
| 26 | 98318643559 |
| 27 | 252713316537 |
[0,23,83,89,287,689,1723,4491,10433,28009,73289, 182043,464679,1196593,3100505,7907085,20156111, 51965647,133805425,342839837,878417801,2258261501, 5808644113,14907781647,38258830449,98318643559, 252713316537] |