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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 11 |
| 4 | 51 |
| 5 | 159 |
| 6 | 727 |
| 7 | 2493 |
| 8 | 11601 |
| 9 | 42313 |
| 10 | 197457 |
| 11 | 752887 |
| 12 | 3527891 |
| 13 | 13829581 |
| 14 | 65034213 |
| 15 | 260677075 |
| 16 | 1228733899 |
| 17 | 5008272491 |
| 18 | 23661262703 |
| 19 | 97742559015 |
| 20 | 462614464051 |
| 21 | 1932210790461 |
| 22 | 9159715949745 |
| 23 | 38607974501823 |
| 24 | 183278075497099 |
| 25 | 778536315711939 |
| 26 | 3700342838461743 |
| 27 | 15823377120013845 |
[1,1,5,11,51,159,727,2493,11601,42313,197457, 752887,3527891,13829581,65034213,260677075, 1228733899,5008272491,23661262703,97742559015, 462614464051,1932210790461,9159715949745, 38607974501823,183278075497099,778536315711939, 3700342838461743,15823377120013845] |