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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 2 |
| 3 | 6 |
| 4 | 10 |
| 5 | 18 |
| 6 | 42 |
| 7 | 78 |
| 8 | 154 |
| 9 | 314 |
| 10 | 626 |
| 11 | 1246 |
| 12 | 2498 |
| 13 | 4994 |
| 14 | 9970 |
| 15 | 19974 |
| 16 | 39930 |
| 17 | 79826 |
| 18 | 159706 |
| 19 | 319374 |
| 20 | 638714 |
| 21 | 1277530 |
| 22 | 2554978 |
| 23 | 5109854 |
| 24 | 10219922 |
| 25 | 20439714 |
| 26 | 40879234 |
| 27 | 81758854 |
| 28 | 163517466 |
| 29 | 327034514 |
| 30 | 654069866 |
| 31 | 1308139246 |
| 32 | 2616277578 |
[1,2,2,6,10,18,42,78,154,314,626,1246,2498,4994, 9970,19974,39930,79826,159706,319374,638714, 1277530,2554978,5109854,10219922,20439714, 40879234,81758854,163517466,327034514,654069866, 1308139246,2616277578] |