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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 5 |
| 4 | 42 |
| 5 | 136 |
| 6 | 2440 |
| 7 | 10900 |
| 8 | 322776 |
| 9 | 1805632 |
| 10 | 77360796 |
| 11 | 514264344 |
| 12 | 29562890886 |
| 13 | 226109935520 |
| 14 | 16604827619828 |
| 15 | 142953007039492 |
| 16 | 12954736337254696 |
| 17 | 123560080110698296 |
| 18 | 13465808369740333664 |
| 19 | 140585883811112551960 |
[1,3,5,42,136,2440,10900,322776,1805632,77360796, 514264344,29562890886,226109935520,16604827619828, 142953007039492,12954736337254696, 123560080110698296,13465808369740333664, 140585883811112551960] |