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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 17 |
| 4 | 57 |
| 5 | 207 |
| 6 | 765 |
| 7 | 2909 |
| 8 | 11291 |
| 9 | 44081 |
| 10 | 175584 |
| 11 | 703093 |
| 12 | 2841402 |
| 13 | 11564076 |
| 14 | 47337597 |
| 15 | 194895967 |
| 16 | 805502604 |
| 17 | 3345308673 |
| 18 | 13940425210 |
| 19 | 58284862481 |
| 20 | 244441854605 |
| 21 | 1027943841626 |
| 22 | 4333816696752 |
| 23 | 18311937717644 |
| 24 | 77543896603410 |
| 25 | 329004496264711 |
| 26 | 1398418407733861 |
| 27 | 5954013641050949 |
[1,2,5,17,57,207,765,2909,11291,44081,175584, 703093,2841402,11564076,47337597,194895967, 805502604,3345308673,13940425210,58284862481, 244441854605,1027943841626,4333816696752, 18311937717644,77543896603410,329004496264711, 1398418407733861,5954013641050949] |