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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 18 |
| 2 | 199 |
| 3 | 2309 |
| 4 | 26660 |
| 5 | 307983 |
| 6 | 3557711 |
| 7 | 41097664 |
| 8 | 474748249 |
| 9 | 5484153915 |
| 10 | 63351353194 |
| 11 | 731816432741 |
| 12 | 8453730886601 |
| 13 | 97655043951558 |
| 14 | 1128082705387895 |
| 15 | 13031283779122753 |
| 16 | 150533605489179940 |
| 17 | 1738920490541077131 |
| 18 | 20087504465180492695 |
| 19 | 232045017488460324836 |
[1,18,199,2309,26660,307983,3557711,41097664, 474748249,5484153915,63351353194,731816432741, 8453730886601,97655043951558,1128082705387895, 13031283779122753,150533605489179940, 1738920490541077131,20087504465180492695, 232045017488460324836] |