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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 7 |
| 6 | 13 |
| 7 | 23 |
| 8 | 41 |
| 9 | 77 |
| 10 | 149 |
| 11 | 397 |
| 12 | 1246 |
| 13 | 21135 |
| 14 | 430933 |
| 15 | 51156773 |
| 16 | 3044120326 |
| 17 | 1704554902881 |
| 18 | 446193132548644 |
| 19 | 650868899188542416 |
| 20 | 431014163502227412545 |
| 21 | 2886915606822315071638459 |
| 22 | 8841362446647790021087061250 |
| 23 | 152946959203764346079534774815394 |
| 24 | 1208238394473886999896406262410758886 |
[0,1,2,4,7,13,23,41,77,149,397,1246,21135,430933, 51156773,3044120326,1704554902881,446193132548644, 650868899188542416,431014163502227412545, 2886915606822315071638459, 8841362446647790021087061250, 152946959203764346079534774815394, 1208238394473886999896406262410758886] |