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| n | a(n) |
|---|---|
| 0 | 6 |
| 1 | 15 |
| 2 | 38 |
| 3 | 97 |
| 4 | 248 |
| 5 | 635 |
| 6 | 1626 |
| 7 | 4164 |
| 8 | 10664 |
| 9 | 27311 |
| 10 | 69945 |
| 11 | 179134 |
| 12 | 458775 |
| 13 | 1174956 |
| 14 | 3009148 |
| 15 | 7706648 |
| 16 | 19737289 |
| 17 | 50548641 |
| 18 | 129458768 |
| 19 | 331553377 |
| 20 | 849132458 |
| 21 | 2174690356 |
| 22 | 5569541124 |
| 23 | 14264002343 |
| 24 | 36531153701 |
| 25 | 93558957622 |
| 26 | 239611336203 |
| 27 | 613662164440 |
| 28 | 1571633704952 |
[6,15,38,97,248,635,1626,4164,10664,27311,69945, 179134,458775,1174956,3009148,7706648,19737289, 50548641,129458768,331553377,849132458,2174690356, 5569541124,14264002343,36531153701,93558957622, 239611336203,613662164440,1571633704952] |