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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 26 |
| 4 | 103 |
| 5 | 427 |
| 6 | 1831 |
| 7 | 8019 |
| 8 | 35703 |
| 9 | 161260 |
| 10 | 736399 |
| 11 | 3391747 |
| 12 | 15739863 |
| 13 | 73517590 |
| 14 | 345214013 |
| 15 | 1628487358 |
| 16 | 7713911678 |
| 17 | 36670988713 |
| 18 | 174874568893 |
| 19 | 836288878658 |
| 20 | 4009503724542 |
| 21 | 19266659826618 |
| 22 | 92770506872980 |
| 23 | 447535198947326 |
| 24 | 2162638003998060 |
| 25 | 10466783750848901 |
| 26 | 50729802575587416 |
| 27 | 246198769403087542 |
[1,2,7,26,103,427,1831,8019,35703,161260,736399, 3391747,15739863,73517590,345214013,1628487358, 7713911678,36670988713,174874568893,836288878658, 4009503724542,19266659826618,92770506872980, 447535198947326,2162638003998060, 10466783750848901,50729802575587416, 246198769403087542] |