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| n | a(n) |
|---|---|
| 1 | 56 |
| 2 | 176 |
| 3 | 792 |
| 4 | 2323520 |
| 5 | 4087968 |
| 6 | 8118264 |
| 7 | 92669720 |
| 8 | 118114304 |
| 9 | 150198136 |
| 10 | 384276336 |
| 11 | 541946240 |
| 12 | 1188908248 |
| 13 | 1844349560 |
| 14 | 2291320912 |
| 15 | 3163127352 |
| 16 | 4351078600 |
| 17 | 5371315400 |
| 18 | 5964539504 |
| 19 | 7346629512 |
| 20 | 10015581680 |
| 21 | 11097645016 |
| 22 | 16670689208 |
| 23 | 18440293320 |
[56,176,792,2323520,4087968,8118264,92669720, 118114304,150198136,384276336,541946240, 1188908248,1844349560,2291320912,3163127352, 4351078600,5371315400,5964539504,7346629512, 10015581680,11097645016,16670689208,18440293320] |