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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 18 |
| 2 | 279 |
| 3 | 4132 |
| 4 | 59949 |
| 5 | 860022 |
| 6 | 12252547 |
| 7 | 173756232 |
| 8 | 2456093529 |
| 9 | 34634926810 |
| 10 | 487525847535 |
| 11 | 6852798238572 |
| 12 | 96216461002117 |
| 13 | 1349689029354558 |
| 14 | 18918661407653979 |
| 15 | 265016591806251664 |
| 16 | 3710426585319049905 |
| 17 | 51924984423522889122 |
| 18 | 726369947645489367751 |
| 19 | 10157588028419864394420 |
[1,18,279,4132,59949,860022,12252547,173756232, 2456093529,34634926810,487525847535,6852798238572, 96216461002117,1349689029354558,18918661407653979, 265016591806251664,3710426585319049905, 51924984423522889122,726369947645489367751, 10157588028419864394420] |