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| n | a(n) |
|---|---|
| 0 | 3 |
| 1 | 14 |
| 2 | 90 |
| 3 | 638 |
| 4 | 4722 |
| 5 | 35894 |
| 6 | 277770 |
| 7 | 2175278 |
| 8 | 17167842 |
| 9 | 136170854 |
| 10 | 1083507450 |
| 11 | 8638762718 |
| 12 | 68963617362 |
| 13 | 550976517014 |
| 14 | 4404150026730 |
| 15 | 35214889666958 |
| 16 | 281627564601282 |
| 17 | 2252562753138374 |
| 18 | 18018213206747610 |
| 19 | 144134261562183998 |
[3,14,90,638,4722,35894,277770,2175278,17167842, 136170854,1083507450,8638762718,68963617362, 550976517014,4404150026730,35214889666958, 281627564601282,2252562753138374, 18018213206747610,144134261562183998] |