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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 9 |
| 2 | 108 |
| 3 | 1458 |
| 4 | 21060 |
| 5 | 318087 |
| 6 | 4960116 |
| 7 | 79227720 |
| 8 | 1289516436 |
| 9 | 21308126895 |
| 10 | 356506456680 |
| 11 | 6027199821864 |
| 12 | 102804351279084 |
| 13 | 1766931074710515 |
| 14 | 30570993847594800 |
| 15 | 532022685332573016 |
| 16 | 9306598678048938420 |
| 17 | 163549467160708850910 |
| 18 | 2886019647490699098588 |
[1,9,108,1458,21060,318087,4960116,79227720, 1289516436,21308126895,356506456680,6027199821864, 102804351279084,1766931074710515, 30570993847594800,532022685332573016, 9306598678048938420,163549467160708850910, 2886019647490699098588] |