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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 2 |
| 3 | 2 |
| 4 | 4 |
| 5 | 8 |
| 6 | 16 |
| 7 | 36 |
| 8 | 74 |
| 9 | 156 |
| 10 | 334 |
| 11 | 706 |
| 12 | 1504 |
| 13 | 3204 |
| 14 | 6828 |
| 15 | 14576 |
| 16 | 31128 |
| 17 | 66524 |
| 18 | 142262 |
| 19 | 304360 |
| 20 | 651456 |
| 21 | 1394894 |
| 22 | 2987672 |
| 23 | 6400950 |
| 24 | 13716916 |
| 25 | 29400542 |
| 26 | 63027304 |
| 27 | 135134330 |
| 28 | 289772558 |
| 29 | 621434722 |
| 30 | 1332826866 |
| 31 | 2858815828 |
| 32 | 6132363430 |
[2,2,2,4,8,16,36,74,156,334,706,1504,3204,6828, 14576,31128,66524,142262,304360,651456,1394894, 2987672,6400950,13716916,29400542,63027304, 135134330,289772558,621434722,1332826866, 2858815828,6132363430] |