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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 0 |
| 6 | 2 |
| 7 | 2 |
| 8 | 5 |
| 9 | 10 |
| 10 | 21 |
| 11 | 46 |
| 12 | 102 |
| 13 | 230 |
| 14 | 526 |
| 15 | 1216 |
| 16 | 2838 |
| 17 | 6678 |
| 18 | 15825 |
| 19 | 37734 |
| 20 | 90469 |
| 21 | 217962 |
| 22 | 527418 |
| 23 | 1281250 |
| 24 | 3123603 |
| 25 | 7639784 |
| 26 | 18740795 |
| 27 | 46096732 |
| 28 | 113666820 |
| 29 | 280928470 |
| 30 | 695796891 |
| 31 | 1726744166 |
| 32 | 4293121609 |
| 33 | 10692145390 |
| 34 | 26671959375 |
| 35 | 66634602702 |
[0,0,0,1,0,2,2,5,10,21,46,102,230,526,1216,2838, 6678,15825,37734,90469,217962,527418,1281250, 3123603,7639784,18740795,46096732,113666820, 280928470,695796891,1726744166,4293121609, 10692145390,26671959375,66634602702] |