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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 9 |
| 3 | 27 |
| 4 | 87 |
| 5 | 351 |
| 6 | 1539 |
| 7 | 6723 |
| 8 | 28467 |
| 9 | 117531 |
| 10 | 479763 |
| 11 | 1955907 |
| 12 | 7998075 |
| 13 | 32807835 |
| 14 | 134797203 |
| 15 | 554013027 |
| 16 | 2276268075 |
| 17 | 9348884811 |
| 18 | 38388273219 |
| 19 | 157620118995 |
| 20 | 647198010171 |
| 21 | 2657558176443 |
| 22 | 10912933399635 |
| 23 | 44813051604675 |
| 24 | 184020663786507 |
| 25 | 755659784907243 |
[1,3,9,27,87,351,1539,6723,28467,117531,479763, 1955907,7998075,32807835,134797203,554013027, 2276268075,9348884811,38388273219,157620118995, 647198010171,2657558176443,10912933399635, 44813051604675,184020663786507,755659784907243] |