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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 6 |
| 2 | 14 |
| 3 | 26 |
| 4 | 54 |
| 5 | 106 |
| 6 | 214 |
| 7 | 426 |
| 8 | 854 |
| 9 | 1706 |
| 10 | 3414 |
| 11 | 6826 |
| 12 | 13654 |
| 13 | 27306 |
| 14 | 54614 |
| 15 | 109226 |
| 16 | 218454 |
| 17 | 436906 |
| 18 | 873814 |
| 19 | 1747626 |
| 20 | 3495254 |
| 21 | 6990506 |
| 22 | 13981014 |
| 23 | 27962026 |
| 24 | 55924054 |
| 25 | 111848106 |
| 26 | 223696214 |
| 27 | 447392426 |
| 28 | 894784854 |
| 29 | 1789569706 |
| 30 | 3579139414 |
[1,6,14,26,54,106,214,426,854,1706,3414,6826, 13654,27306,54614,109226,218454,436906,873814, 1747626,3495254,6990506,13981014,27962026, 55924054,111848106,223696214,447392426,894784854, 1789569706,3579139414] |