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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 16 |
| 5 | 39 |
| 6 | 100 |
| 7 | 248 |
| 8 | 618 |
| 9 | 1546 |
| 10 | 3858 |
| 11 | 9631 |
| 12 | 24049 |
| 13 | 60041 |
| 14 | 149903 |
| 15 | 374266 |
| 16 | 934427 |
| 17 | 2332981 |
| 18 | 5824753 |
| 19 | 14542648 |
| 20 | 36308602 |
| 21 | 90651625 |
| 22 | 226329747 |
| 23 | 565077072 |
| 24 | 1410826915 |
| 25 | 3522409024 |
| 26 | 8794392287 |
| 27 | 21956943442 |
| 28 | 54819861280 |
| 29 | 136868649264 |
[1,1,2,7,16,39,100,248,618,1546,3858,9631,24049, 60041,149903,374266,934427,2332981,5824753, 14542648,36308602,90651625,226329747,565077072, 1410826915,3522409024,8794392287,21956943442, 54819861280,136868649264] |