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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 3 |
| 3 | 7 |
| 4 | 19 |
| 5 | 94 |
| 6 | 381 |
| 7 | 2217 |
| 8 | 10248 |
| 9 | 64082 |
| 10 | 572741 |
| 11 | 3590815 |
| 12 | 33731134 |
| 13 | 291308123 |
| 14 | 1896596488 |
| 15 | 14675287694 |
| 16 | 147847569839 |
| 17 | 1642854121867 |
| 18 | 12717640104203 |
| 19 | 134707566446733 |
| 20 | 1285768348848054 |
| 21 | 9334472487460317 |
| 22 | 97284913917125312 |
| 23 | 922382339920122509 |
| 24 | 10370484766702974615 |
[1,2,3,7,19,94,381,2217,10248,64082,572741, 3590815,33731134,291308123,1896596488,14675287694, 147847569839,1642854121867,12717640104203, 134707566446733,1285768348848054,9334472487460317, 97284913917125312,922382339920122509, 10370484766702974615] |