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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 12 |
| 4 | 52 |
| 5 | 232 |
| 6 | 1049 |
| 7 | 4777 |
| 8 | 21845 |
| 9 | 100159 |
| 10 | 460023 |
| 11 | 2115350 |
| 12 | 9735205 |
| 13 | 44829766 |
| 14 | 206526972 |
| 15 | 951759621 |
| 16 | 4387156587 |
| 17 | 20226421380 |
| 18 | 93264500832 |
| 19 | 430091815527 |
| 20 | 1983549213861 |
| 21 | 9148582037193 |
| 22 | 42197572190160 |
| 23 | 194643215702835 |
[1,1,3,12,52,232,1049,4777,21845,100159,460023, 2115350,9735205,44829766,206526972,951759621, 4387156587,20226421380,93264500832,430091815527, 1983549213861,9148582037193,42197572190160, 194643215702835] |