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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 12 |
| 4 | 38 |
| 5 | 76 |
| 6 | 188 |
| 7 | 376 |
| 8 | 1094 |
| 9 | 2188 |
| 10 | 5236 |
| 11 | 10472 |
| 12 | 26076 |
| 13 | 52152 |
| 14 | 118840 |
| 15 | 237680 |
| 16 | 612678 |
| 17 | 1225356 |
| 18 | 2804420 |
| 19 | 5608840 |
| 20 | 13279604 |
| 21 | 26559208 |
| 22 | 59074504 |
| 23 | 118149008 |
| 24 | 277925148 |
| 25 | 555850296 |
| 26 | 1228260104 |
| 27 | 2456520208 |
| 28 | 5552652792 |
| 29 | 11105305584 |
[1,2,6,12,38,76,188,376,1094,2188,5236,10472, 26076,52152,118840,237680,612678,1225356,2804420, 5608840,13279604,26559208,59074504,118149008, 277925148,555850296,1228260104,2456520208, 5552652792,11105305584] |