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| n | a(n) |
|---|---|
| 0 | 2 |
| 1 | 5 |
| 2 | 8 |
| 3 | 22 |
| 4 | 47 |
| 5 | 103 |
| 6 | 234 |
| 7 | 493 |
| 8 | 1087 |
| 9 | 2282 |
| 10 | 4901 |
| 11 | 10427 |
| 12 | 21993 |
| 13 | 46389 |
| 14 | 97394 |
| 15 | 204567 |
| 16 | 427099 |
| 17 | 892587 |
| 18 | 1858338 |
| 19 | 3865692 |
| 20 | 8027140 |
| 21 | 16642918 |
| 22 | 34463760 |
| 23 | 71273199 |
| 24 | 147235636 |
| 25 | 303814862 |
| 26 | 626313383 |
| 27 | 1289883519 |
| 28 | 2654196000 |
[2,5,8,22,47,103,234,493,1087,2282,4901,10427, 21993,46389,97394,204567,427099,892587,1858338, 3865692,8027140,16642918,34463760,71273199, 147235636,303814862,626313383,1289883519, 2654196000] |