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| n | a(n) |
|---|---|
| 1 | 64 |
| 2 | 178 |
| 3 | 690 |
| 4 | 3698 |
| 5 | 19434 |
| 6 | 99458 |
| 7 | 510378 |
| 8 | 2622050 |
| 9 | 13507474 |
| 10 | 69549218 |
| 11 | 357584194 |
| 12 | 1839211250 |
| 13 | 9464568582 |
| 14 | 48696339042 |
| 15 | 250509806670 |
| 16 | 1288779804242 |
| 17 | 6630621737430 |
| 18 | 34113122683362 |
| 19 | 175501749819570 |
| 20 | 902909367872738 |
[64,178,690,3698,19434,99458,510378,2622050, 13507474,69549218,357584194,1839211250,9464568582, 48696339042,250509806670,1288779804242, 6630621737430,34113122683362,175501749819570, 902909367872738] |