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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 3 |
| 5 | 6 |
| 6 | 6 |
| 7 | 18 |
| 8 | 18 |
| 9 | 26 |
| 10 | 26 |
| 11 | 73 |
| 12 | 73 |
| 13 | 179 |
| 14 | 179 |
| 15 | 459 |
| 16 | 459 |
| 17 | 1179 |
| 18 | 1179 |
| 19 | 3004 |
| 20 | 3004 |
| 21 | 8111 |
| 22 | 8111 |
| 23 | 22183 |
| 24 | 22183 |
| 25 | 60789 |
| 26 | 60789 |
| 27 | 168641 |
| 28 | 168641 |
| 29 | 469689 |
| 30 | 469689 |
| 31 | 1322664 |
| 32 | 1322664 |
| 33 | 3691761 |
| 34 | 3691761 |
| 35 | 10390938 |
| 36 | 10390938 |
| 37 | 29502559 |
| 38 | 29502559 |
| 39 | 84012658 |
| 40 | 84012658 |
| 41 | 239417332 |
| 42 | 239417332 |
[1,1,3,3,6,6,18,18,26,26,73,73,179,179,459,459, 1179,1179,3004,3004,8111,8111,22183,22183,60789, 60789,168641,168641,469689,469689,1322664,1322664, 3691761,3691761,10390938,10390938,29502559, 29502559,84012658,84012658,239417332,239417332] |