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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 3 |
| 4 | 24 |
| 5 | 7 |
| 6 | 112 |
| 7 | 15 |
| 8 | 480 |
| 9 | 31 |
| 10 | 1984 |
| 11 | 63 |
| 12 | 4480 |
| 13 | 1151 |
| 14 | 29440 |
| 15 | 255 |
| 16 | 114176 |
| 17 | 33279 |
| 18 | 453632 |
| 19 | 132095 |
| 20 | 1120256 |
| 21 | 100351 |
| 22 | 7106560 |
| 23 | 2494463 |
| 24 | 25190400 |
| 25 | 16261119 |
| 26 | 100712448 |
| 27 | 8929279 |
| 28 | 402882560 |
| 29 | 257982463 |
| 30 | 1612382208 |
| 31 | 809566207 |
| 32 | 4348837888 |
| 33 | 134348799 |
| 34 | 31878545408 |
[1,1,4,3,24,7,112,15,480,31,1984,63,4480,1151, 29440,255,114176,33279,453632,132095,1120256, 100351,7106560,2494463,25190400,16261119, 100712448,8929279,402882560,257982463,1612382208, 809566207,4348837888,134348799,31878545408] |