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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 4 |
| 4 | 23 |
| 5 | 27 |
| 6 | 50 |
| 7 | 77 |
| 8 | 281 |
| 9 | 1482 |
| 10 | 3245 |
| 11 | 30687 |
| 12 | 248741 |
| 13 | 2269356 |
| 14 | 4787453 |
| 15 | 26206621 |
| 16 | 83407316 |
| 17 | 109613937 |
| 18 | 193021253 |
| 19 | 302635190 |
| 20 | 1706197203 |
| 21 | 2008832393 |
| 22 | 5723861989 |
| 23 | 7732694382 |
| 24 | 438754747381 |
| 25 | 446487441763 |
| 26 | 1331729630907 |
| 27 | 1778217072670 |
| 28 | 10222814994257 |
[1,1,3,4,23,27,50,77,281,1482,3245,30687,248741, 2269356,4787453,26206621,83407316,109613937, 193021253,302635190,1706197203,2008832393, 5723861989,7732694382,438754747381,446487441763, 1331729630907,1778217072670,10222814994257] |