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| n | a(n) |
|---|---|
| 1 | 10 |
| 2 | 90 |
| 3 | 616 |
| 4 | 3731 |
| 5 | 20208 |
| 6 | 102665 |
| 7 | 492118 |
| 8 | 2275947 |
| 9 | 10175908 |
| 10 | 44549594 |
| 11 | 190996160 |
| 12 | 808576340 |
| 13 | 3377247432 |
| 14 | 13999854480 |
| 15 | 57518174798 |
| 16 | 235275969669 |
| 17 | 956569084218 |
| 18 | 3879844758272 |
| 19 | 15670308778784 |
| 20 | 63219573247523 |
| 21 | 254277270362900 |
[10,90,616,3731,20208,102665,492118,2275947, 10175908,44549594,190996160,808576340,3377247432, 13999854480,57518174798,235275969669,956569084218, 3879844758272,15670308778784,63219573247523, 254277270362900] |