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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 2 |
| 2 | 4 |
| 3 | 20 |
| 4 | 32 |
| 5 | 256 |
| 6 | 416 |
| 7 | 4832 |
| 8 | 8192 |
| 9 | 42496 |
| 10 | 74752 |
| 11 | 1467392 |
| 12 | 2650112 |
| 13 | 62836736 |
| 14 | 115552256 |
| 15 | 42790912 |
| 16 | 79691776 |
| 17 | 2535587840 |
| 18 | 4766040064 |
| 19 | 170851041280 |
| 20 | 1617069867008 |
| 21 | 3070050172928 |
| 22 | 5843921666048 |
| 23 | 256460544016384 |
| 24 | 490390373269504 |
| 25 | 4697678227177472 |
| 26 | 9016382767235072 |
[0,2,4,20,32,256,416,4832,8192,42496,74752, 1467392,2650112,62836736,115552256,42790912, 79691776,2535587840,4766040064,170851041280, 1617069867008,3070050172928,5843921666048, 256460544016384,490390373269504,4697678227177472, 9016382767235072] |