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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 1 |
| 7 | 3 |
| 8 | 8 |
| 9 | 19 |
| 10 | 40 |
| 11 | 83 |
| 12 | 176 |
| 13 | 365 |
| 14 | 775 |
| 15 | 1643 |
| 16 | 3483 |
| 17 | 7299 |
| 18 | 15170 |
| 19 | 31010 |
| 20 | 62563 |
| 21 | 124221 |
| 22 | 243296 |
| 23 | 469856 |
| 24 | 896491 |
| 25 | 1690475 |
| 26 | 3155551 |
| 27 | 5834871 |
| 28 | 10701036 |
| 29 | 19479021 |
| 30 | 35227889 |
| 31 | 63335778 |
| 32 | 113286272 |
| 33 | 201687929 |
| 34 | 357585904 |
| 35 | 631574315 |
| 36 | 1111614614 |
| 37 | 1950096758 |
| 38 | 3410420973 |
| 39 | 5946337698 |
| 40 | 10337420278 |
| 41 | 17918573379 |
| 42 | 30968896662 |
| 43 | 53366449357 |
| 44 | 91689380979 |
| 45 | 157058043025 |
| 46 | 268210414468 |
| 47 | 456613323892 |
[0,0,0,0,0,0,1,3,8,19,40,83,176,365,775,1643,3483, 7299,15170,31010,62563,124221,243296,469856, 896491,1690475,3155551,5834871,10701036,19479021, 35227889,63335778,113286272,201687929,357585904, 631574315,1111614614,1950096758,3410420973, 5946337698,10337420278,17918573379,30968896662, 53366449357,91689380979,157058043025,268210414468, 456613323892] |