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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 7 |
| 4 | 18 |
| 5 | 21 |
| 6 | 66 |
| 7 | 71 |
| 8 | 196 |
| 9 | 305 |
| 10 | 648 |
| 11 | 1035 |
| 12 | 2526 |
| 13 | 4109 |
| 14 | 8774 |
| 15 | 16875 |
| 16 | 34288 |
| 17 | 65553 |
| 18 | 134860 |
| 19 | 262163 |
| 20 | 531506 |
| 21 | 1051237 |
| 22 | 2109594 |
| 23 | 4194327 |
| 24 | 8425348 |
| 25 | 16779257 |
| 26 | 33611984 |
| 27 | 67123631 |
| 28 | 134350206 |
| 29 | 268435485 |
| 30 | 537178750 |
| 31 | 1073741855 |
| 32 | 2148064768 |
| 33 | 4295048345 |
| 34 | 8591114580 |
[1,4,7,18,21,66,71,196,305,648,1035,2526,4109, 8774,16875,34288,65553,134860,262163,531506, 1051237,2109594,4194327,8425348,16779257,33611984, 67123631,134350206,268435485,537178750,1073741855, 2148064768,4295048345,8591114580] |