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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 9 |
| 3 | 21 |
| 4 | 45 |
| 5 | 93 |
| 6 | 189 |
| 7 | 381 |
| 8 | 765 |
| 9 | 1533 |
| 10 | 3069 |
| 11 | 6141 |
| 12 | 12285 |
| 13 | 24573 |
| 14 | 49149 |
| 15 | 98301 |
| 16 | 196605 |
| 17 | 393213 |
| 18 | 786429 |
| 19 | 1572861 |
| 20 | 3145725 |
| 21 | 6291453 |
| 22 | 12582909 |
| 23 | 25165821 |
| 24 | 50331645 |
| 25 | 100663293 |
| 26 | 201326589 |
| 27 | 402653181 |
| 28 | 805306365 |
| 29 | 1610612733 |
[1,3,9,21,45,93,189,381,765,1533,3069,6141,12285, 24573,49149,98301,196605,393213,786429,1572861, 3145725,6291453,12582909,25165821,50331645, 100663293,201326589,402653181,805306365, 1610612733] |