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| n | a(n) |
|---|---|
| 1 | 510 |
| 2 | 3150 |
| 3 | 18160 |
| 4 | 107510 |
| 5 | 629790 |
| 6 | 3704980 |
| 7 | 21758550 |
| 8 | 127872530 |
| 9 | 751278240 |
| 10 | 4414434310 |
| 11 | 25937520830 |
| 12 | 152401930300 |
| 13 | 895465610130 |
| 14 | 5261491036130 |
| 15 | 30914921038320 |
| 16 | 181646780968570 |
| 17 | 1067301604632450 |
| 18 | 6271142423909740 |
[510,3150,18160,107510,629790,3704980,21758550, 127872530,751278240,4414434310,25937520830, 152401930300,895465610130,5261491036130, 30914921038320,181646780968570,1067301604632450, 6271142423909740] |