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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 9 |
| 4 | 46 |
| 5 | 117 |
| 6 | 636 |
| 7 | 2596 |
| 8 | 13343 |
| 9 | 66452 |
| 10 | 354806 |
| 11 | 1898800 |
| 12 | 10452050 |
| 13 | 58080269 |
| 14 | 327389928 |
| 15 | 1863061322 |
| 16 | 10707246833 |
| 17 | 62028855007 |
| 18 | 362078074528 |
| 19 | 2127680924575 |
| 20 | 12580327500008 |
| 21 | 74800656700824 |
| 22 | 447053889525102 |
| 23 | 2684568476124840 |
| 24 | 16191874238303244 |
[1,6,9,46,117,636,2596,13343,66452,354806,1898800, 10452050,58080269,327389928,1863061322, 10707246833,62028855007,362078074528, 2127680924575,12580327500008,74800656700824, 447053889525102,2684568476124840, 16191874238303244] |