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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 21 |
| 5 | 71 |
| 6 | 213 |
| 7 | 564 |
| 8 | 1340 |
| 9 | 2909 |
| 10 | 5860 |
| 11 | 11090 |
| 12 | 19911 |
| 13 | 34179 |
| 14 | 56447 |
| 15 | 90144 |
| 16 | 139782 |
| 17 | 211193 |
| 18 | 311798 |
| 19 | 450910 |
| 20 | 640073 |
| 21 | 893439 |
| 22 | 1228185 |
| 23 | 1664972 |
| 24 | 2228448 |
| 25 | 2947797 |
| 26 | 3857336 |
| 27 | 4997162 |
| 28 | 6413851 |
| 29 | 8161211 |
| 30 | 10301091 |
| 31 | 12904248 |
| 32 | 16051274 |
| 33 | 19833585 |
| 34 | 24354474 |
| 35 | 29730230 |
[1,2,6,21,71,213,564,1340,2909,5860,11090,19911, 34179,56447,90144,139782,211193,311798,450910, 640073,893439,1228185,1664972,2228448,2947797, 3857336,4997162,6413851,8161211,10301091,12904248, 16051274,19833585,24354474,29730230] |