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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 17 |
| 4 | 60 |
| 5 | 211 |
| 6 | 788 |
| 7 | 3087 |
| 8 | 12031 |
| 9 | 47612 |
| 10 | 193723 |
| 11 | 793555 |
| 12 | 3259183 |
| 13 | 13568871 |
| 14 | 57057573 |
| 15 | 240409463 |
| 16 | 1018554059 |
| 17 | 4350518045 |
| 18 | 18652248413 |
| 19 | 80161322115 |
| 20 | 346233726610 |
| 21 | 1501989852179 |
| 22 | 6529325778008 |
| 23 | 28460597180882 |
| 24 | 124509570144503 |
| 25 | 546038156698710 |
| 26 | 2398821135999848 |
| 27 | 10564714909607449 |
[1,2,5,17,60,211,788,3087,12031,47612,193723, 793555,3259183,13568871,57057573,240409463, 1018554059,4350518045,18652248413,80161322115, 346233726610,1501989852179,6529325778008, 28460597180882,124509570144503,546038156698710, 2398821135999848,10564714909607449] |