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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 23 |
| 5 | 75 |
| 6 | 238 |
| 7 | 800 |
| 8 | 2734 |
| 9 | 9417 |
| 10 | 33207 |
| 11 | 117661 |
| 12 | 421563 |
| 13 | 1524047 |
| 14 | 5537482 |
| 15 | 20269868 |
| 16 | 74545781 |
| 17 | 275422975 |
| 18 | 1022213776 |
| 19 | 3806863892 |
| 20 | 14227928563 |
| 21 | 53338307668 |
| 22 | 200505927183 |
| 23 | 755722398596 |
| 24 | 2854949775551 |
| 25 | 10808994805493 |
| 26 | 41006118620478 |
| 27 | 155852743565206 |
| 28 | 593389348239315 |
| 29 | 2262898414661276 |
[1,1,3,8,23,75,238,800,2734,9417,33207,117661, 421563,1524047,5537482,20269868,74545781, 275422975,1022213776,3806863892,14227928563, 53338307668,200505927183,755722398596, 2854949775551,10808994805493,41006118620478, 155852743565206,593389348239315,2262898414661276] |