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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 12 |
| 3 | 49 |
| 4 | 198 |
| 5 | 792 |
| 6 | 3170 |
| 7 | 12681 |
| 8 | 50727 |
| 9 | 202909 |
| 10 | 811636 |
| 11 | 3246545 |
| 12 | 12986183 |
| 13 | 51944732 |
| 14 | 207778928 |
| 15 | 831115713 |
| 16 | 3324462855 |
| 17 | 13297851421 |
| 18 | 53191405684 |
| 19 | 212765622737 |
| 20 | 851062490950 |
| 21 | 3404249963800 |
| 22 | 13616999855201 |
| 23 | 54467999420806 |
| 24 | 217871997683226 |
| 25 | 871487990732903 |
[3,12,49,198,792,3170,12681,50727,202909,811636, 3246545,12986183,51944732,207778928,831115713, 3324462855,13297851421,53191405684,212765622737, 851062490950,3404249963800,13616999855201, 54467999420806,217871997683226,871487990732903] |