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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 28 |
| 5 | 91 |
| 6 | 353 |
| 7 | 1313 |
| 8 | 5279 |
| 9 | 21233 |
| 10 | 87974 |
| 11 | 369069 |
| 12 | 1572716 |
| 13 | 6763787 |
| 14 | 29462557 |
| 15 | 129147912 |
| 16 | 571417218 |
| 17 | 2543626341 |
| 18 | 11393262275 |
| 19 | 51321889995 |
| 20 | 232283468959 |
| 21 | 1056120669869 |
| 22 | 4821911290022 |
| 23 | 22095113714613 |
| 24 | 101606770406224 |
| 25 | 468712264973306 |
| 26 | 2168546809906870 |
| 27 | 10060820614451701 |
| 28 | 46793794711248079 |
[1,1,3,8,28,91,353,1313,5279,21233,87974,369069, 1572716,6763787,29462557,129147912,571417218, 2543626341,11393262275,51321889995,232283468959, 1056120669869,4821911290022,22095113714613, 101606770406224,468712264973306,2168546809906870, 10060820614451701,46793794711248079] |