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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 13 |
| 4 | 38 |
| 5 | 127 |
| 6 | 439 |
| 7 | 1561 |
| 8 | 5673 |
| 9 | 21144 |
| 10 | 81137 |
| 11 | 314145 |
| 12 | 1232603 |
| 13 | 4909110 |
| 14 | 19728702 |
| 15 | 80154126 |
| 16 | 327820102 |
| 17 | 1350493841 |
| 18 | 5610705828 |
| 19 | 23416574546 |
| 20 | 98304768279 |
| 21 | 414909948960 |
| 22 | 1758260345077 |
| 23 | 7488145688244 |
| 24 | 32001010966712 |
| 25 | 137249426117898 |
| 26 | 590954969322700 |
| 27 | 2551267808790323 |
| 28 | 11049608193888765 |
[1,2,5,13,38,127,439,1561,5673,21144,81137,314145, 1232603,4909110,19728702,80154126,327820102, 1350493841,5610705828,23416574546,98304768279, 414909948960,1758260345077,7488145688244, 32001010966712,137249426117898,590954969322700, 2551267808790323,11049608193888765] |