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| n | a(n) |
|---|---|
| 1 | 48 |
| 2 | 330 |
| 3 | 1336 |
| 4 | 4204 |
| 5 | 12376 |
| 6 | 35520 |
| 7 | 101096 |
| 8 | 291658 |
| 9 | 847968 |
| 10 | 2515656 |
| 11 | 7544020 |
| 12 | 23042956 |
| 13 | 71066182 |
| 14 | 222455898 |
| 15 | 701643848 |
| 16 | 2238614428 |
| 17 | 7182380086 |
| 18 | 23244437414 |
| 19 | 75523460968 |
| 20 | 246963498566 |
| 21 | 809749533116 |
| 22 | 2667549489664 |
| 23 | 8803343561560 |
[48,330,1336,4204,12376,35520,101096,291658, 847968,2515656,7544020,23042956,71066182, 222455898,701643848,2238614428,7182380086, 23244437414,75523460968,246963498566,809749533116, 2667549489664,8803343561560] |