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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 2 |
| 4 | 7 |
| 5 | 25 |
| 6 | 6 |
| 7 | 22 |
| 8 | 81 |
| 9 | 299 |
| 10 | 24 |
| 11 | 90 |
| 12 | 338 |
| 13 | 1271 |
| 14 | 4785 |
| 15 | 120 |
| 16 | 456 |
| 17 | 1734 |
| 18 | 6598 |
| 19 | 25121 |
| 20 | 95699 |
| 21 | 720 |
| 22 | 2760 |
| 23 | 10584 |
| 24 | 40602 |
| 25 | 155810 |
| 26 | 598119 |
| 27 | 2296777 |
| 28 | 5040 |
| 29 | 19440 |
| 30 | 75000 |
| 31 | 289416 |
| 32 | 1117062 |
| 33 | 4312438 |
| 34 | 16651633 |
| 35 | 64309755 |
| 36 | 40320 |
| 37 | 156240 |
| 38 | 605520 |
| 39 | 2347080 |
| 40 | 9098904 |
| 41 | 35278554 |
| 42 | 136801778 |
| 43 | 530555479 |
| 44 | 2057912161 |
[1,1,3,2,7,25,6,22,81,299,24,90,338,1271,4785,120, 456,1734,6598,25121,95699,720,2760,10584,40602, 155810,598119,2296777,5040,19440,75000,289416, 1117062,4312438,16651633,64309755,40320,156240, 605520,2347080,9098904,35278554,136801778, 530555479,2057912161] |