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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 8 |
| 6 | 17 |
| 7 | 36 |
| 8 | 78 |
| 9 | 168 |
| 10 | 364 |
| 11 | 786 |
| 12 | 1700 |
| 13 | 3668 |
| 14 | 7916 |
| 15 | 17056 |
| 16 | 36729 |
| 17 | 78996 |
| 18 | 169772 |
| 19 | 364472 |
| 20 | 781814 |
| 21 | 1675464 |
| 22 | 3587660 |
| 23 | 7675722 |
| 24 | 16409240 |
| 25 | 35052552 |
| 26 | 74822496 |
| 27 | 159599700 |
| 28 | 340199178 |
| 29 | 724675528 |
| 30 | 1542673868 |
| 31 | 3281957116 |
| 32 | 6977971852 |
| 33 | 14827596904 |
| 34 | 31489490296 |
| 35 | 66837617960 |
| 36 | 141789447876 |
| 37 | 300636048724 |
| 38 | 637116434912 |
| 39 | 1349532001896 |
| 40 | 2857195771769 |
| 41 | 6046370298448 |
[1,0,1,2,4,8,17,36,78,168,364,786,1700,3668,7916, 17056,36729,78996,169772,364472,781814,1675464, 3587660,7675722,16409240,35052552,74822496, 159599700,340199178,724675528,1542673868, 3281957116,6977971852,14827596904,31489490296, 66837617960,141789447876,300636048724, 637116434912,1349532001896,2857195771769, 6046370298448] |