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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 27 |
| 4 | 116 |
| 5 | 475 |
| 6 | 2093 |
| 7 | 9225 |
| 8 | 41812 |
| 9 | 190557 |
| 10 | 881483 |
| 11 | 4100209 |
| 12 | 19231374 |
| 13 | 90670058 |
| 14 | 429730691 |
| 15 | 2044916451 |
| 16 | 9768824521 |
| 17 | 46811676808 |
| 18 | 224969448854 |
| 19 | 1083897615629 |
| 20 | 5233923365141 |
| 21 | 25324373396373 |
| 22 | 122757487998436 |
| 23 | 596026077271773 |
| 24 | 2898222779227043 |
| 25 | 14112145883113578 |
| 26 | 68800737149631772 |
[1,2,8,27,116,475,2093,9225,41812,190557,881483, 4100209,19231374,90670058,429730691,2044916451, 9768824521,46811676808,224969448854,1083897615629, 5233923365141,25324373396373,122757487998436, 596026077271773,2898222779227043, 14112145883113578,68800737149631772] |