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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 19 |
| 4 | 67 |
| 5 | 217 |
| 6 | 721 |
| 7 | 2377 |
| 8 | 7855 |
| 9 | 25939 |
| 10 | 85675 |
| 11 | 282961 |
| 12 | 934561 |
| 13 | 3086641 |
| 14 | 10194487 |
| 15 | 33670099 |
| 16 | 111204787 |
| 17 | 367284457 |
| 18 | 1213058161 |
| 19 | 4006458937 |
| 20 | 13232434975 |
| 21 | 43703763859 |
| 22 | 144343726555 |
| 23 | 476734943521 |
| 24 | 1574548557121 |
| 25 | 5200380614881 |
[1,7,19,67,217,721,2377,7855,25939,85675,282961, 934561,3086641,10194487,33670099,111204787, 367284457,1213058161,4006458937,13232434975, 43703763859,144343726555,476734943521, 1574548557121,5200380614881] |