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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 4 |
| 5 | 4 |
| 6 | 12 |
| 7 | 19 |
| 8 | 30 |
| 9 | 43 |
| 10 | 102 |
| 11 | 159 |
| 12 | 340 |
| 13 | 537 |
| 14 | 1146 |
| 15 | 1914 |
| 16 | 3992 |
| 17 | 6378 |
| 18 | 14010 |
| 19 | 23145 |
| 20 | 49682 |
| 21 | 82295 |
| 22 | 180016 |
| 23 | 303833 |
| 24 | 654049 |
| 25 | 1098521 |
| 26 | 2387358 |
| 27 | 4075501 |
| 28 | 8820563 |
| 29 | 15062515 |
| 30 | 32732736 |
| 31 | 56401388 |
| 32 | 121964573 |
| 33 | 210680037 |
[1,2,2,4,4,12,19,30,43,102,159,340,537,1146,1914, 3992,6378,14010,23145,49682,82295,180016,303833, 654049,1098521,2387358,4075501,8820563,15062515, 32732736,56401388,121964573,210680037] |