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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 9 |
| 4 | 18 |
| 5 | 37 |
| 6 | 70 |
| 7 | 128 |
| 8 | 225 |
| 9 | 383 |
| 10 | 633 |
| 11 | 1019 |
| 12 | 1601 |
| 13 | 2461 |
| 14 | 3711 |
| 15 | 5494 |
| 16 | 8003 |
| 17 | 11484 |
| 18 | 16249 |
| 19 | 22698 |
| 20 | 31328 |
| 21 | 42762 |
| 22 | 57764 |
| 23 | 77274 |
| 24 | 102436 |
| 25 | 134634 |
| 26 | 175532 |
| 27 | 227123 |
| 28 | 291776 |
| 29 | 372300 |
| 30 | 472004 |
[1,2,4,9,18,37,70,128,225,383,633,1019,1601,2461, 3711,5494,8003,11484,16249,22698,31328,42762, 57764,77274,102436,134634,175532,227123,291776, 372300,472004] |