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| n | a(n) |
|---|---|
| 1 | 8 |
| 2 | 65 |
| 3 | 425 |
| 4 | 2931 |
| 5 | 19363 |
| 6 | 129974 |
| 7 | 871345 |
| 8 | 5848852 |
| 9 | 39278049 |
| 10 | 263713497 |
| 11 | 1770482001 |
| 12 | 11887215402 |
| 13 | 79812178186 |
| 14 | 535861305908 |
| 15 | 3597799009537 |
| 16 | 24155860662607 |
| 17 | 162183882073432 |
| 18 | 1088911875204984 |
| 19 | 7311018935280645 |
| 20 | 49086615774849387 |
[8,65,425,2931,19363,129974,871345,5848852, 39278049,263713497,1770482001,11887215402, 79812178186,535861305908,3597799009537, 24155860662607,162183882073432,1088911875204984, 7311018935280645,49086615774849387] |