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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 3 |
| 3 | 4 |
| 4 | 8 |
| 5 | 15 |
| 6 | 26 |
| 7 | 45 |
| 8 | 79 |
| 9 | 139 |
| 10 | 244 |
| 11 | 428 |
| 12 | 751 |
| 13 | 1318 |
| 14 | 2313 |
| 15 | 4059 |
| 16 | 7123 |
| 17 | 12500 |
| 18 | 21936 |
| 19 | 38495 |
| 20 | 67554 |
| 21 | 118549 |
| 22 | 208039 |
| 23 | 365083 |
| 24 | 640676 |
| 25 | 1124308 |
| 26 | 1973023 |
| 27 | 3462414 |
| 28 | 6076113 |
| 29 | 10662835 |
| 30 | 18711971 |
| 31 | 32837220 |
| 32 | 57625304 |
| 33 | 101125359 |
[1,3,3,4,8,15,26,45,79,139,244,428,751,1318,2313, 4059,7123,12500,21936,38495,67554,118549,208039, 365083,640676,1124308,1973023,3462414,6076113, 10662835,18711971,32837220,57625304,101125359] |