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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 7 |
| 2 | 36 |
| 3 | 162 |
| 4 | 675 |
| 5 | 2673 |
| 6 | 10206 |
| 7 | 37908 |
| 8 | 137781 |
| 9 | 492075 |
| 10 | 1732104 |
| 11 | 6022998 |
| 12 | 20726199 |
| 13 | 70681653 |
| 14 | 239148450 |
| 15 | 803538792 |
| 16 | 2683245609 |
| 17 | 8910671247 |
| 18 | 29443957164 |
| 19 | 96855122250 |
| 20 | 317297380491 |
| 21 | 1035574967097 |
| 22 | 3368233731366 |
| 23 | 10920608743932 |
| 24 | 35303692060125 |
| 25 | 113819103201843 |
[1,7,36,162,675,2673,10206,37908,137781,492075, 1732104,6022998,20726199,70681653,239148450, 803538792,2683245609,8910671247,29443957164, 96855122250,317297380491,1035574967097, 3368233731366,10920608743932,35303692060125, 113819103201843] |