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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 6 |
| 4 | 11 |
| 5 | 18 |
| 6 | 33 |
| 7 | 58 |
| 8 | 102 |
| 9 | 182 |
| 10 | 324 |
| 11 | 578 |
| 12 | 1030 |
| 13 | 1836 |
| 14 | 3272 |
| 15 | 5832 |
| 16 | 10397 |
| 17 | 18533 |
| 18 | 33036 |
| 19 | 58890 |
| 20 | 104976 |
| 21 | 187131 |
| 22 | 333580 |
| 23 | 594640 |
| 24 | 1060006 |
| 25 | 1889568 |
| 26 | 3368349 |
| 27 | 6004427 |
| 28 | 10703506 |
| 29 | 19080095 |
| 30 | 34012224 |
| 31 | 60630275 |
[1,2,4,6,11,18,33,58,102,182,324,578,1030,1836, 3272,5832,10397,18533,33036,58890,104976,187131, 333580,594640,1060006,1889568,3368349,6004427, 10703506,19080095,34012224,60630275] |