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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 15 |
| 5 | 39 |
| 6 | 127 |
| 7 | 405 |
| 8 | 1330 |
| 9 | 4478 |
| 10 | 15574 |
| 11 | 54337 |
| 12 | 194625 |
| 13 | 700396 |
| 14 | 2559981 |
| 15 | 9426329 |
| 16 | 35084696 |
| 17 | 131480551 |
| 18 | 496179720 |
| 19 | 1884859504 |
| 20 | 7203732487 |
| 21 | 27668398667 |
| 22 | 106846816154 |
| 23 | 414250796495 |
| 24 | 1613369878006 |
| 25 | 6307760507487 |
| 26 | 24749075122327 |
| 27 | 97443934965134 |
| 28 | 384830938765071 |
| 29 | 1524409052733699 |
| 30 | 6055634647599138 |
[1,1,2,5,15,39,127,405,1330,4478,15574,54337, 194625,700396,2559981,9426329,35084696,131480551, 496179720,1884859504,7203732487,27668398667, 106846816154,414250796495,1613369878006, 6307760507487,24749075122327,97443934965134, 384830938765071,1524409052733699,6055634647599138] |