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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 8 |
| 3 | 19 |
| 4 | 42 |
| 5 | 85 |
| 6 | 174 |
| 7 | 353 |
| 8 | 712 |
| 9 | 1431 |
| 10 | 2864 |
| 11 | 5743 |
| 12 | 11492 |
| 13 | 22989 |
| 14 | 45982 |
| 15 | 91971 |
| 16 | 183968 |
| 17 | 367939 |
| 18 | 735888 |
| 19 | 1471789 |
| 20 | 2943596 |
| 21 | 5887195 |
| 22 | 11774408 |
| 23 | 23548837 |
| 24 | 47097690 |
| 25 | 94195387 |
| 26 | 188390808 |
| 27 | 376781617 |
| 28 | 753563240 |
| 29 | 1507126509 |
| 30 | 3014253028 |
[1,3,8,19,42,85,174,353,712,1431,2864,5743,11492, 22989,45982,91971,183968,367939,735888,1471789, 2943596,5887195,11774408,23548837,47097690, 94195387,188390808,376781617,753563240,1507126509, 3014253028] |