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| n | a(n) |
|---|---|
| 1 | 11 |
| 2 | 45 |
| 3 | 185 |
| 4 | 812 |
| 5 | 4298 |
| 6 | 19935 |
| 7 | 102113 |
| 8 | 524113 |
| 9 | 2687777 |
| 10 | 14197596 |
| 11 | 74308295 |
| 12 | 393206009 |
| 13 | 2088107591 |
| 14 | 11086538469 |
| 15 | 59103852278 |
| 16 | 315153667732 |
| 17 | 1682280633028 |
| 18 | 8989204931719 |
| 19 | 48042619335921 |
| 20 | 256910321615776 |
| 21 | 1374182610970469 |
[11,45,185,812,4298,19935,102113,524113,2687777, 14197596,74308295,393206009,2088107591, 11086538469,59103852278,315153667732, 1682280633028,8989204931719,48042619335921, 256910321615776,1374182610970469] |