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| n | a(n) |
|---|---|
| 1 | 16 |
| 2 | 42 |
| 3 | 308 |
| 4 | 1664 |
| 5 | 10246 |
| 6 | 60804 |
| 7 | 368220 |
| 8 | 2217012 |
| 9 | 13380802 |
| 10 | 80716652 |
| 11 | 487004728 |
| 12 | 2938281242 |
| 13 | 17727888682 |
| 14 | 106960361186 |
| 15 | 645338542928 |
| 16 | 3893618011484 |
| 17 | 23491925716860 |
| 18 | 141737303076720 |
| 19 | 855164357481732 |
| 20 | 5159588643396442 |
[16,42,308,1664,10246,60804,368220,2217012, 13380802,80716652,487004728,2938281242, 17727888682,106960361186,645338542928, 3893618011484,23491925716860,141737303076720, 855164357481732,5159588643396442] |