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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 23 |
| 4 | 96 |
| 5 | 412 |
| 6 | 1819 |
| 7 | 8165 |
| 8 | 37244 |
| 9 | 172041 |
| 10 | 802068 |
| 11 | 3766707 |
| 12 | 17797247 |
| 13 | 84512353 |
| 14 | 403062511 |
| 15 | 1929377961 |
| 16 | 9264898815 |
| 17 | 44613567669 |
| 18 | 215353482998 |
| 19 | 1041777792180 |
| 20 | 5049322884229 |
| 21 | 24515402802290 |
| 22 | 119211717497632 |
| 23 | 580509003433142 |
| 24 | 2830439159149030 |
| 25 | 13816713360019538 |
| 26 | 67517940619384443 |
[1,2,6,23,96,412,1819,8165,37244,172041,802068, 3766707,17797247,84512353,403062511,1929377961, 9264898815,44613567669,215353482998,1041777792180, 5049322884229,24515402802290,119211717497632, 580509003433142,2830439159149030, 13816713360019538,67517940619384443] |