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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 7 |
| 5 | 15 |
| 6 | 38 |
| 7 | 79 |
| 8 | 184 |
| 9 | 378 |
| 10 | 823 |
| 11 | 1682 |
| 12 | 3552 |
| 13 | 7208 |
| 14 | 14948 |
| 15 | 30154 |
| 16 | 61698 |
| 17 | 124302 |
| 18 | 252125 |
| 19 | 506521 |
| 20 | 1022768 |
| 21 | 2051555 |
| 22 | 4127633 |
| 23 | 8272147 |
| 24 | 16607469 |
| 25 | 33258510 |
| 26 | 66680774 |
| 27 | 133467385 |
| 28 | 267349211 |
| 29 | 535007304 |
| 30 | 1071020315 |
| 31 | 2142778192 |
| 32 | 4288207796 |
[0,0,1,2,7,15,38,79,184,378,823,1682,3552,7208, 14948,30154,61698,124302,252125,506521,1022768, 2051555,4127633,8272147,16607469,33258510, 66680774,133467385,267349211,535007304,1071020315, 2142778192,4288207796] |