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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 8 |
| 4 | 20 |
| 5 | 64 |
| 6 | 172 |
| 7 | 512 |
| 8 | 1416 |
| 9 | 4096 |
| 10 | 11468 |
| 11 | 32768 |
| 12 | 92248 |
| 13 | 262144 |
| 14 | 739832 |
| 15 | 2097152 |
| 16 | 5925520 |
| 17 | 16777216 |
| 18 | 47429900 |
| 19 | 134217728 |
| 20 | 379536440 |
| 21 | 1073741824 |
| 22 | 3036661032 |
| 23 | 8589934592 |
| 24 | 24294699120 |
| 25 | 68719476736 |
| 26 | 194363001272 |
[0,1,2,8,20,64,172,512,1416,4096,11468,32768, 92248,262144,739832,2097152,5925520,16777216, 47429900,134217728,379536440,1073741824, 3036661032,8589934592,24294699120,68719476736, 194363001272] |