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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 6 |
| 3 | 13 |
| 4 | 21 |
| 5 | 73 |
| 6 | 98 |
| 7 | 521 |
| 8 | 636 |
| 9 | 4721 |
| 10 | 5439 |
| 11 | 53323 |
| 12 | 59318 |
| 13 | 737183 |
| 14 | 801235 |
| 15 | 12215237 |
| 16 | 13068626 |
| 17 | 238205651 |
| 18 | 251987681 |
| 19 | 5381022817 |
| 20 | 5644769560 |
| 21 | 138933578143 |
| 22 | 144807081479 |
| 23 | 4053430178401 |
| 24 | 4203399920996 |
| 25 | 132332669898119 |
| 26 | 136669373292795 |
| 27 | 4793783797371011 |
[3,6,13,21,73,98,521,636,4721,5439,53323,59318, 737183,801235,12215237,13068626,238205651, 251987681,5381022817,5644769560,138933578143, 144807081479,4053430178401,4203399920996, 132332669898119,136669373292795,4793783797371011] |