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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 65 |
| 4 | 521 |
| 5 | 4168 |
| 6 | 33345 |
| 7 | 266761 |
| 8 | 2134088 |
| 9 | 17072705 |
| 10 | 136581641 |
| 11 | 1092653128 |
| 12 | 8741225025 |
| 13 | 69929800201 |
| 14 | 559438401608 |
| 15 | 4475507212865 |
| 16 | 35804057702921 |
| 17 | 286432461623368 |
| 18 | 2291459692986945 |
| 19 | 18331677543895561 |
| 20 | 146653420351164488 |
| 21 | 1173227362809315905 |
| 22 | 9385818902474527241 |
[1,8,65,521,4168,33345,266761,2134088,17072705, 136581641,1092653128,8741225025,69929800201, 559438401608,4475507212865,35804057702921, 286432461623368,2291459692986945, 18331677543895561,146653420351164488, 1173227362809315905,9385818902474527241] |