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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 0 |
| 5 | 3 |
| 6 | 1 |
| 7 | 28 |
| 8 | 0 |
| 9 | 28 |
| 10 | 281 |
| 11 | 120 |
| 12 | 1680 |
| 13 | 0 |
| 14 | 840 |
| 15 | 9921 |
| 16 | 139376 |
| 17 | 29760 |
| 18 | 277760 |
| 19 | 0 |
| 20 | 83328 |
| 21 | 16078337 |
| 22 | 20000736 |
| 23 | 140491008 |
| 24 | 19998720 |
| 25 | 139991040 |
| 26 | 0 |
| 27 | 27998208 |
| 28 | 13596908545 |
| 29 | 130684723136 |
| 30 | 81282991104 |
| 31 | 380636971008 |
| 32 | 40637399040 |
| 33 | 227569434624 |
| 34 | 0 |
| 35 | 32509919232 |
| 36 | 191426147495937 |
| 37 | 443803094908800 |
| 38 | 2132774681579520 |
| 39 | 884358943211520 |
| 40 | 3105997683425280 |
| 41 | 265280940933120 |
| 42 | 1237977724354560 |
| 43 | 0 |
| 44 | 132640470466560 |
[1,0,1,1,0,3,1,28,0,28,281,120,1680,0,840,9921, 139376,29760,277760,0,83328,16078337,20000736, 140491008,19998720,139991040,0,27998208, 13596908545,130684723136,81282991104,380636971008, 40637399040,227569434624,0,32509919232, 191426147495937,443803094908800,2132774681579520, 884358943211520,3105997683425280,265280940933120, 1237977724354560,0,132640470466560] |