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| n | a(n) |
|---|---|
| 21 | 1 |
| 22 | 22 |
| 23 | 253 |
| 24 | 2024 |
| 25 | 12650 |
| 26 | 65780 |
| 27 | 296010 |
| 28 | 1184040 |
| 29 | 4292145 |
| 30 | 14307150 |
| 31 | 44352165 |
| 32 | 129024480 |
| 33 | 354817320 |
| 34 | 927983760 |
| 35 | 2319959400 |
| 36 | 5567902560 |
| 37 | 12875774670 |
| 38 | 28781143380 |
| 39 | 62359143990 |
| 40 | 131282408400 |
| 41 | 269128937220 |
| 42 | 538257874440 |
| 43 | 1052049481860 |
| 44 | 2012616400080 |
| 45 | 3773655750150 |
[1,22,253,2024,12650,65780,296010,1184040,4292145, 14307150,44352165,129024480,354817320,927983760, 2319959400,5567902560,12875774670,28781143380, 62359143990,131282408400,269128937220, 538257874440,1052049481860,2012616400080, 3773655750150] |