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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 86 |
| 4 | 776 |
| 5 | 7010 |
| 6 | 63674 |
| 7 | 578090 |
| 8 | 5247824 |
| 9 | 47640092 |
| 10 | 432480632 |
| 11 | 3926091512 |
| 12 | 35641352528 |
| 13 | 323554871864 |
| 14 | 2937255393440 |
| 15 | 26664624744320 |
| 16 | 242063463190976 |
| 17 | 2197470272854016 |
| 18 | 19948799940346880 |
| 19 | 181096701955896896 |
| 20 | 1644009442040416928 |
| 21 | 14924441010395894048 |
| 22 | 135485194778650515104 |
[1,8,86,776,7010,63674,578090,5247824,47640092, 432480632,3926091512,35641352528,323554871864, 2937255393440,26664624744320,242063463190976, 2197470272854016,19948799940346880, 181096701955896896,1644009442040416928, 14924441010395894048,135485194778650515104] |