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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 7 |
| 3 | 19 |
| 4 | 52 |
| 5 | 165 |
| 6 | 835 |
| 7 | 3307 |
| 8 | 14419 |
| 9 | 66213 |
| 10 | 302731 |
| 11 | 1350601 |
| 12 | 6283864 |
| 13 | 28864821 |
| 14 | 132830017 |
| 15 | 617677553 |
| 16 | 2862431936 |
| 17 | 13363660417 |
| 18 | 62171655121 |
| 19 | 291908874951 |
| 20 | 1362607426103 |
| 21 | 6418589261153 |
| 22 | 30080186463929 |
| 23 | 142028701850239 |
[3,7,19,52,165,835,3307,14419,66213,302731, 1350601,6283864,28864821,132830017,617677553, 2862431936,13363660417,62171655121,291908874951, 1362607426103,6418589261153,30080186463929, 142028701850239] |