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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 4 |
| 5 | 10 |
| 6 | 20 |
| 7 | 36 |
| 8 | 64 |
| 9 | 120 |
| 10 | 240 |
| 11 | 496 |
| 12 | 1024 |
| 13 | 2080 |
| 14 | 4160 |
| 15 | 8255 |
| 16 | 16368 |
| 17 | 32504 |
| 18 | 64464 |
| 19 | 126940 |
| 20 | 246640 |
| 21 | 470536 |
| 22 | 879056 |
| 23 | 1607862 |
| 24 | 2886800 |
| 25 | 5117800 |
| 26 | 9046960 |
| 27 | 16166475 |
| 28 | 29666676 |
| 29 | 56666754 |
| 30 | 113330260 |
| 31 | 236315636 |
| 32 | 507817728 |
| 33 | 1109184992 |
| 34 | 2433554624 |
| 35 | 5318390075 |
[0,0,1,4,10,20,36,64,120,240,496,1024,2080,4160, 8255,16368,32504,64464,126940,246640,470536, 879056,1607862,2886800,5117800,9046960,16166475, 29666676,56666754,113330260,236315636,507817728, 1109184992,2433554624,5318390075] |