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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 23 |
| 3 | 47 |
| 4 | 237 |
| 5 | 765 |
| 6 | 3284 |
| 7 | 14482 |
| 8 | 53272 |
| 9 | 215514 |
| 10 | 912084 |
| 11 | 3648248 |
| 12 | 14687047 |
| 13 | 60203513 |
| 14 | 245335061 |
| 15 | 994616646 |
| 16 | 4046916244 |
| 17 | 16494072611 |
| 18 | 67083379987 |
| 19 | 272827461209 |
| 20 | 1110711231219 |
| 21 | 4520415462039 |
| 22 | 18391763438584 |
| 23 | 74846658443216 |
[3,23,47,237,765,3284,14482,53272,215514,912084, 3648248,14687047,60203513,245335061,994616646, 4046916244,16494072611,67083379987,272827461209, 1110711231219,4520415462039,18391763438584, 74846658443216] |