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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 27 |
| 4 | 122 |
| 5 | 499 |
| 6 | 2214 |
| 7 | 9842 |
| 8 | 44530 |
| 9 | 203920 |
| 10 | 940733 |
| 11 | 4372177 |
| 12 | 20483297 |
| 13 | 96217438 |
| 14 | 454871743 |
| 15 | 2156838988 |
| 16 | 10261591892 |
| 17 | 48987161073 |
| 18 | 234370298197 |
| 19 | 1124216923471 |
| 20 | 5404012596212 |
| 21 | 26022531847774 |
| 22 | 125547200108280 |
| 23 | 606608973049013 |
| 24 | 2935239954436866 |
| 25 | 14222485466148384 |
| 26 | 68994436275698448 |
[1,2,8,27,122,499,2214,9842,44530,203920,940733, 4372177,20483297,96217438,454871743,2156838988, 10261591892,48987161073,234370298197, 1124216923471,5404012596212,26022531847774, 125547200108280,606608973049013,2935239954436866, 14222485466148384,68994436275698448] |