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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 4 |
| 3 | 3 |
| 4 | 20 |
| 5 | 19 |
| 6 | 64 |
| 7 | 63 |
| 8 | 368 |
| 9 | 495 |
| 10 | 1952 |
| 11 | 735 |
| 12 | 5696 |
| 13 | 6207 |
| 14 | 26368 |
| 15 | 3327 |
| 16 | 116992 |
| 17 | 767 |
| 18 | 520704 |
| 19 | 229887 |
| 20 | 1210368 |
| 21 | 47103 |
| 22 | 8230912 |
| 23 | 1521663 |
| 24 | 28446720 |
| 25 | 15052799 |
| 26 | 72146944 |
| 27 | 42491903 |
| 28 | 307675136 |
| 29 | 5488639 |
| 30 | 2128707584 |
| 31 | 1050181631 |
| 32 | 4681236480 |
| 33 | 2598502399 |
| 34 | 17617649664 |
[1,0,4,3,20,19,64,63,368,495,1952,735,5696,6207, 26368,3327,116992,767,520704,229887,1210368,47103, 8230912,1521663,28446720,15052799,72146944, 42491903,307675136,5488639,2128707584,1050181631, 4681236480,2598502399,17617649664] |