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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 5 |
| 6 | 12 |
| 7 | 25 |
| 8 | 64 |
| 9 | 166 |
| 10 | 405 |
| 11 | 1050 |
| 12 | 2763 |
| 13 | 7239 |
| 14 | 19190 |
| 15 | 51457 |
| 16 | 138538 |
| 17 | 374972 |
| 18 | 1020943 |
| 19 | 2792183 |
| 20 | 7666358 |
| 21 | 21126905 |
| 22 | 58422650 |
| 23 | 162052566 |
| 24 | 450742451 |
| 25 | 1256974690 |
| 26 | 3513731861 |
| 27 | 9843728012 |
| 28 | 27633400879 |
| 29 | 77721141911 |
| 30 | 218984204904 |
| 31 | 618021576627 |
| 32 | 1746906189740 |
| 33 | 4945026080426 |
| 34 | 14017220713131 |
[0,0,1,1,2,5,12,25,64,166,405,1050,2763,7239, 19190,51457,138538,374972,1020943,2792183,7666358, 21126905,58422650,162052566,450742451,1256974690, 3513731861,9843728012,27633400879,77721141911, 218984204904,618021576627,1746906189740, 4945026080426,14017220713131] |