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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 39 |
| 5 | 144 |
| 6 | 530 |
| 7 | 1987 |
| 8 | 7455 |
| 9 | 28268 |
| 10 | 107334 |
| 11 | 410354 |
| 12 | 1570954 |
| 13 | 6042984 |
| 14 | 23273172 |
| 15 | 89948835 |
| 16 | 348000975 |
| 17 | 1350028020 |
| 18 | 5241881150 |
| 19 | 20396787070 |
| 20 | 79426533758 |
| 21 | 309829067496 |
| 22 | 1209384071532 |
| 23 | 4727454837846 |
| 24 | 18490127530394 |
[1,3,11,39,144,530,1987,7455,28268,107334,410354, 1570954,6042984,23273172,89948835,348000975, 1350028020,5241881150,20396787070,79426533758, 309829067496,1209384071532,4727454837846, 18490127530394] |