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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 15 |
| 5 | 31 |
| 6 | 63 |
| 7 | 126 |
| 8 | 246 |
| 9 | 465 |
| 10 | 847 |
| 11 | 1485 |
| 12 | 2509 |
| 13 | 4095 |
| 14 | 6475 |
| 15 | 9948 |
| 16 | 14892 |
| 17 | 21777 |
| 18 | 31179 |
| 19 | 43795 |
| 20 | 60459 |
| 21 | 82159 |
| 22 | 110055 |
| 23 | 145498 |
| 24 | 190050 |
| 25 | 245505 |
| 26 | 313911 |
| 27 | 397593 |
| 28 | 499177 |
| 29 | 621615 |
| 30 | 768211 |
| 31 | 942648 |
| 32 | 1149016 |
| 33 | 1391841 |
| 34 | 1676115 |
| 35 | 2007327 |
| 36 | 2391495 |
[0,1,3,7,15,31,63,126,246,465,847,1485,2509,4095, 6475,9948,14892,21777,31179,43795,60459,82159, 110055,145498,190050,245505,313911,397593,499177, 621615,768211,942648,1149016,1391841,1676115, 2007327,2391495] |