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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 16 |
| 5 | 62 |
| 6 | 192 |
| 7 | 652 |
| 8 | 2048 |
| 9 | 9270 |
| 10 | 31744 |
| 11 | 116948 |
| 12 | 393216 |
| 13 | 1533868 |
| 14 | 5341184 |
| 15 | 19445016 |
| 16 | 67108864 |
| 17 | 332958758 |
| 18 | 1215037440 |
| 19 | 4711687300 |
| 20 | 16642998272 |
| 21 | 67697833092 |
| 22 | 245257732096 |
| 23 | 923984441000 |
| 24 | 3298534883328 |
| 25 | 13952454631996 |
[1,2,6,16,62,192,652,2048,9270,31744,116948, 393216,1533868,5341184,19445016,67108864, 332958758,1215037440,4711687300,16642998272, 67697833092,245257732096,923984441000, 3298534883328,13952454631996] |