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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 20 |
| 3 | 315 |
| 4 | 280 |
| 5 | 66 |
| 6 | 3003 |
| 7 | 78 |
| 8 | 9520 |
| 9 | 305235 |
| 10 | 20900 |
| 11 | 138 |
| 12 | 19734 |
| 13 | 6 |
| 14 | 7540 |
| 15 | 15575175 |
| 16 | 590240 |
| 17 | 6 |
| 18 | 107666559 |
| 19 | 222 |
| 20 | 11996600 |
| 21 | 50536395 |
| 22 | 19780 |
| 23 | 282 |
| 24 | 31534932 |
| 25 | 66 |
| 26 | 1060 |
| 27 | 48532365 |
| 28 | 738920 |
| 29 | 354 |
| 30 | 83912718435 |
| 31 | 366 |
| 32 | 1180480 |
| 33 | 485415 |
| 34 | 1340 |
| 35 | 60918 |
| 36 | 3667092237666 |
| 37 | 438 |
| 38 | 740 |
[6,20,315,280,66,3003,78,9520,305235,20900,138, 19734,6,7540,15575175,590240,6,107666559,222, 11996600,50536395,19780,282,31534932,66,1060, 48532365,738920,354,83912718435,366,1180480, 485415,1340,60918,3667092237666,438,740] |