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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 29 |
| 4 | 131 |
| 5 | 572 |
| 6 | 2448 |
| 7 | 10341 |
| 8 | 43288 |
| 9 | 180003 |
| 10 | 744712 |
| 11 | 3068793 |
| 12 | 12605411 |
| 13 | 51642528 |
| 14 | 211110240 |
| 15 | 861409918 |
| 16 | 3509341245 |
| 17 | 14277424978 |
| 18 | 58017460260 |
| 19 | 235512889296 |
| 20 | 955146370152 |
| 21 | 3870511127394 |
| 22 | 15672817355658 |
| 23 | 63421721139479 |
| 24 | 256488917828150 |
| 25 | 1036722699748068 |
| 26 | 4188329011110360 |
[1,6,29,131,572,2448,10341,43288,180003,744712, 3068793,12605411,51642528,211110240,861409918, 3509341245,14277424978,58017460260,235512889296, 955146370152,3870511127394,15672817355658, 63421721139479,256488917828150,1036722699748068, 4188329011110360] |