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| n | a(n) |
|---|---|
| 2 | 0 |
| 3 | 2 |
| 4 | 4 |
| 5 | 12 |
| 6 | 20 |
| 7 | 52 |
| 8 | 100 |
| 9 | 214 |
| 10 | 414 |
| 11 | 876 |
| 12 | 1722 |
| 13 | 3524 |
| 14 | 6992 |
| 15 | 14144 |
| 16 | 28188 |
| 17 | 56720 |
| 18 | 113180 |
| 19 | 227084 |
| 20 | 453748 |
| 21 | 908804 |
| 22 | 1816726 |
| 23 | 3636336 |
| 24 | 7270770 |
| 25 | 14547228 |
| 26 | 29090912 |
| 27 | 58192994 |
| 28 | 116378984 |
| 29 | 232780848 |
| 30 | 465546796 |
| 31 | 931139720 |
| 32 | 1862251212 |
| 33 | 3724592874 |
| 34 | 7449128940 |
| 35 | 14898442336 |
| 36 | 29796768552 |
[0,2,4,12,20,52,100,214,414,876,1722,3524,6992, 14144,28188,56720,113180,227084,453748,908804, 1816726,3636336,7270770,14547228,29090912, 58192994,116378984,232780848,465546796,931139720, 1862251212,3724592874,7449128940,14898442336, 29796768552] |