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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 12 |
| 3 | 32 |
| 4 | 93 |
| 5 | 288 |
| 6 | 926 |
| 7 | 3048 |
| 8 | 10209 |
| 9 | 34694 |
| 10 | 119271 |
| 11 | 413844 |
| 12 | 1446881 |
| 13 | 5090694 |
| 14 | 18007935 |
| 15 | 64000106 |
| 16 | 228389088 |
| 17 | 817976316 |
| 18 | 2939029154 |
| 19 | 10590554976 |
[6,12,32,93,288,926,3048,10209,34694,119271, 413844,1446881,5090694,18007935,64000106, 228389088,817976316,2939029154,10590554976] |