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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 12 |
| 3 | 31 |
| 4 | 109 |
| 5 | 397 |
| 6 | 1430 |
| 7 | 5110 |
| 8 | 18395 |
| 9 | 66203 |
| 10 | 238103 |
| 11 | 856413 |
| 12 | 3081033 |
| 13 | 11083994 |
| 14 | 39873749 |
| 15 | 143444250 |
| 16 | 516038048 |
| 17 | 1856433397 |
| 18 | 6678469130 |
| 19 | 24025629692 |
| 20 | 86431623758 |
| 21 | 310935653685 |
| 22 | 1118583441105 |
| 23 | 4024076800534 |
| 24 | 14476518656548 |
[1,12,31,109,397,1430,5110,18395,66203,238103, 856413,3081033,11083994,39873749,143444250, 516038048,1856433397,6678469130,24025629692, 86431623758,310935653685,1118583441105, 4024076800534,14476518656548] |