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| n | a(n) |
|---|---|
| 1 | 13 |
| 2 | 18 |
| 3 | 41 |
| 4 | 55 |
| 5 | 136 |
| 6 | 345 |
| 7 | 842 |
| 8 | 2167 |
| 9 | 5544 |
| 10 | 14244 |
| 11 | 36572 |
| 12 | 94381 |
| 13 | 243153 |
| 14 | 629090 |
| 15 | 1626951 |
| 16 | 4215276 |
| 17 | 10927245 |
| 18 | 28335336 |
| 19 | 73504819 |
| 20 | 190696269 |
| 21 | 494767839 |
| 22 | 1283719592 |
| 23 | 3330784937 |
| 24 | 8642038996 |
| 25 | 22422738925 |
| 26 | 58177733612 |
| 27 | 150947560518 |
[13,18,41,55,136,345,842,2167,5544,14244,36572, 94381,243153,629090,1626951,4215276,10927245, 28335336,73504819,190696269,494767839,1283719592, 3330784937,8642038996,22422738925,58177733612, 150947560518] |