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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 38 |
| 5 | 192 |
| 6 | 1152 |
| 7 | 8068 |
| 8 | 64549 |
| 9 | 580947 |
| 10 | 5809475 |
| 11 | 63904227 |
| 12 | 766850734 |
| 13 | 9969059549 |
| 14 | 139566833690 |
| 15 | 2093502505354 |
| 16 | 33496040085671 |
| 17 | 569432681456423 |
| 18 | 10249788266215622 |
| 19 | 194745977058096830 |
| 20 | 3894919541161936616 |
[1,3,9,38,192,1152,8068,64549,580947,5809475, 63904227,766850734,9969059549,139566833690, 2093502505354,33496040085671,569432681456423, 10249788266215622,194745977058096830, 3894919541161936616] |