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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 23 |
| 5 | 75 |
| 6 | 263 |
| 7 | 859 |
| 8 | 3027 |
| 9 | 10847 |
| 10 | 40277 |
| 11 | 148941 |
| 12 | 558955 |
| 13 | 2091905 |
| 14 | 7964021 |
| 15 | 30592053 |
| 16 | 118488259 |
| 17 | 459892963 |
| 18 | 1797038297 |
| 19 | 7045304575 |
| 20 | 27753725487 |
| 21 | 109797374923 |
| 22 | 436241707057 |
| 23 | 1738515110135 |
| 24 | 6952220014915 |
| 25 | 27871651746743 |
| 26 | 111995783605643 |
| 27 | 451202149489489 |
| 28 | 1822864384511955 |
[1,1,3,7,23,75,263,859,3027,10847,40277,148941, 558955,2091905,7964021,30592053,118488259, 459892963,1797038297,7045304575,27753725487, 109797374923,436241707057,1738515110135, 6952220014915,27871651746743,111995783605643, 451202149489489,1822864384511955] |