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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 10 |
| 5 | 27 |
| 6 | 109 |
| 7 | 168 |
| 8 | 349 |
| 9 | 1229 |
| 10 | 2490 |
| 11 | 4767 |
| 12 | 14401 |
| 13 | 33504 |
| 14 | 66377 |
| 15 | 175249 |
| 16 | 433386 |
| 17 | 909235 |
| 18 | 2208549 |
| 19 | 5522840 |
| 20 | 12201285 |
| 21 | 28458341 |
| 22 | 70294586 |
| 23 | 161026423 |
| 24 | 370622297 |
| 25 | 898784848 |
| 26 | 2102285073 |
| 27 | 4841334921 |
| 28 | 11557476010 |
| 29 | 27287134763 |
| 30 | 63194732573 |
[1,3,9,10,27,109,168,349,1229,2490,4767,14401, 33504,66377,175249,433386,909235,2208549,5522840, 12201285,28458341,70294586,161026423,370622297, 898784848,2102285073,4841334921,11557476010, 27287134763,63194732573] |