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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 7 |
| 3 | 17 |
| 4 | 37 |
| 5 | 83 |
| 6 | 181 |
| 7 | 399 |
| 8 | 863 |
| 9 | 1887 |
| 10 | 4057 |
| 11 | 8797 |
| 12 | 18851 |
| 13 | 40649 |
| 14 | 86911 |
| 15 | 186705 |
| 16 | 398413 |
| 17 | 853407 |
| 18 | 1818099 |
| 19 | 3885377 |
| 20 | 8266359 |
| 21 | 17632961 |
| 22 | 37473467 |
| 23 | 79814011 |
| 24 | 169457991 |
| 25 | 360469139 |
| 26 | 764700473 |
| 27 | 1624915019 |
| 28 | 3444615545 |
| 29 | 7312733017 |
| 30 | 15492242679 |
| 31 | 32862908109 |
| 32 | 69581860921 |
| 33 | 147497088201 |
[1,3,7,17,37,83,181,399,863,1887,4057,8797,18851, 40649,86911,186705,398413,853407,1818099,3885377, 8266359,17632961,37473467,79814011,169457991, 360469139,764700473,1624915019,3444615545, 7312733017,15492242679,32862908109,69581860921, 147497088201] |