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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 11 |
| 4 | 36 |
| 5 | 125 |
| 6 | 451 |
| 7 | 1627 |
| 8 | 6114 |
| 9 | 23313 |
| 10 | 89669 |
| 11 | 349271 |
| 12 | 1377492 |
| 13 | 5467197 |
| 14 | 21844772 |
| 15 | 87937757 |
| 16 | 355984774 |
| 17 | 1447373061 |
| 18 | 5912845467 |
| 19 | 24259828873 |
| 20 | 99881034250 |
| 21 | 412575338505 |
| 22 | 1709751683474 |
| 23 | 7105421773773 |
| 24 | 29603546104182 |
| 25 | 123641970713669 |
| 26 | 517589863523413 |
| 27 | 2171211944958415 |
| 28 | 9125656546345446 |
[1,1,4,11,36,125,451,1627,6114,23313,89669,349271, 1377492,5467197,21844772,87937757,355984774, 1447373061,5912845467,24259828873,99881034250, 412575338505,1709751683474,7105421773773, 29603546104182,123641970713669,517589863523413, 2171211944958415,9125656546345446] |