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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 12 |
| 3 | 49 |
| 4 | 199 |
| 5 | 796 |
| 6 | 3185 |
| 7 | 12743 |
| 8 | 50972 |
| 9 | 203889 |
| 10 | 815559 |
| 11 | 3262236 |
| 12 | 13048945 |
| 13 | 52195783 |
| 14 | 208783132 |
| 15 | 835132529 |
| 16 | 3340530119 |
| 17 | 13362120476 |
| 18 | 53448481905 |
| 19 | 213793927623 |
| 20 | 855175710492 |
| 21 | 3420702841969 |
| 22 | 13682811367879 |
| 23 | 54731245471516 |
[3,12,49,199,796,3185,12743,50972,203889,815559, 3262236,13048945,52195783,208783132,835132529, 3340530119,13362120476,53448481905,213793927623, 855175710492,3420702841969,13682811367879, 54731245471516] |