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| n | a(n) |
|---|---|
| 1 | 18 |
| 2 | 70 |
| 3 | 88 |
| 4 | 132 |
| 5 | 780 |
| 6 | 11096 |
| 7 | 17816 |
| 8 | 518656 |
| 9 | 1713592 |
| 10 | 9928792 |
| 11 | 11547352 |
| 12 | 13499120 |
| 13 | 17999992 |
| 14 | 89283592 |
| 15 | 134094848 |
| 16 | 173482552 |
| 17 | 175519344 |
| 18 | 318836720 |
| 19 | 903230984 |
| 20 | 1081850752 |
| 21 | 2146926592 |
| 22 | 16709332608 |
| 23 | 18543186000 |
| 24 | 34177937500 |
[18,70,88,132,780,11096,17816,518656,1713592, 9928792,11547352,13499120,17999992,89283592, 134094848,173482552,175519344,318836720,903230984, 1081850752,2146926592,16709332608,18543186000, 34177937500] |