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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 42 |
| 6 | 131 |
| 7 | 417 |
| 8 | 1341 |
| 9 | 4334 |
| 10 | 14041 |
| 11 | 45542 |
| 12 | 147798 |
| 13 | 479779 |
| 14 | 1557649 |
| 15 | 5057369 |
| 16 | 16420730 |
| 17 | 53317085 |
| 18 | 173118414 |
| 19 | 562110290 |
| 20 | 1825158051 |
| 21 | 5926246929 |
| 22 | 19242396629 |
| 23 | 62479659622 |
| 24 | 202870165265 |
| 25 | 658715265222 |
| 26 | 2138834994142 |
| 27 | 6944753544643 |
| 28 | 22549473023585 |
[1,1,2,5,14,42,131,417,1341,4334,14041,45542, 147798,479779,1557649,5057369,16420730,53317085, 173118414,562110290,1825158051,5926246929, 19242396629,62479659622,202870165265,658715265222, 2138834994142,6944753544643,22549473023585] |