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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 19 |
| 5 | 86 |
| 6 | 436 |
| 7 | 2378 |
| 8 | 13731 |
| 9 | 83077 |
| 10 | 523275 |
| 11 | 3416329 |
| 12 | 23051600 |
| 13 | 160440679 |
| 14 | 1150435934 |
| 15 | 8492238919 |
| 16 | 64508971958 |
| 17 | 504172573079 |
| 18 | 4053925852485 |
| 19 | 33535370139607 |
| 20 | 285391912938870 |
| 21 | 2498255748837089 |
| 22 | 22489737035242848 |
| 23 | 208124346717364948 |
| 24 | 1978949027666465869 |
| 25 | 19321957528006663637 |
| 26 | 193581292284734286398 |
| 27 | 1988536950750112238165 |
[1,1,2,5,19,86,436,2378,13731,83077,523275, 3416329,23051600,160440679,1150435934,8492238919, 64508971958,504172573079,4053925852485, 33535370139607,285391912938870,2498255748837089, 22489737035242848,208124346717364948, 1978949027666465869,19321957528006663637, 193581292284734286398,1988536950750112238165] |