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| n | a(n) |
|---|---|
| 5 | 1 |
| 6 | 0 |
| 7 | 0 |
| 8 | 0 |
| 9 | 4 |
| 10 | 9 |
| 11 | 10 |
| 12 | 11 |
| 13 | 34 |
| 14 | 91 |
| 15 | 196 |
| 16 | 330 |
| 17 | 636 |
| 18 | 1377 |
| 19 | 2976 |
| 20 | 6061 |
| 21 | 12199 |
| 22 | 25186 |
| 23 | 52767 |
| 24 | 109066 |
| 25 | 224964 |
| 26 | 467605 |
| 27 | 979056 |
| 28 | 2042847 |
| 29 | 4244986 |
| 30 | 8844130 |
| 31 | 18527956 |
| 32 | 38878929 |
| 33 | 81460220 |
| 34 | 170576593 |
| 35 | 357894472 |
| 36 | 752544917 |
| 37 | 1583579674 |
| 38 | 3332453026 |
| 39 | 7016669752 |
| 40 | 14790212086 |
[1,0,0,0,4,9,10,11,34,91,196,330,636,1377,2976, 6061,12199,25186,52767,109066,224964,467605, 979056,2042847,4244986,8844130,18527956,38878929, 81460220,170576593,357894472,752544917,1583579674, 3332453026,7016669752,14790212086] |