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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 7 |
| 4 | 19 |
| 5 | 37 |
| 6 | 115 |
| 7 | 361 |
| 8 | 937 |
| 9 | 2599 |
| 10 | 7777 |
| 11 | 22195 |
| 12 | 62701 |
| 13 | 182647 |
| 14 | 531829 |
| 15 | 1534903 |
| 16 | 4461571 |
| 17 | 13034917 |
| 18 | 38015899 |
| 19 | 110994193 |
| 20 | 325011151 |
| 21 | 952442557 |
| 22 | 2792471239 |
| 23 | 8198275933 |
| 24 | 24093817531 |
| 25 | 70852613041 |
| 26 | 208516575043 |
| 27 | 614145137137 |
[1,1,1,7,19,37,115,361,937,2599,7777,22195,62701, 182647,531829,1534903,4461571,13034917,38015899, 110994193,325011151,952442557,2792471239, 8198275933,24093817531,70852613041,208516575043, 614145137137] |