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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 28 |
| 5 | 91 |
| 6 | 339 |
| 7 | 1219 |
| 8 | 4701 |
| 9 | 17939 |
| 10 | 71573 |
| 11 | 284089 |
| 12 | 1157733 |
| 13 | 4721259 |
| 14 | 19569779 |
| 15 | 81402649 |
| 16 | 342160546 |
| 17 | 1445001223 |
| 18 | 6145007988 |
| 19 | 26261712426 |
| 20 | 112789021222 |
| 21 | 486638853729 |
| 22 | 2107738866605 |
| 23 | 9165837675101 |
| 24 | 39988572047898 |
| 25 | 175057214787952 |
| 26 | 768550521307934 |
| 27 | 3383830890482911 |
| 28 | 14937351793963389 |
[1,1,3,8,28,91,339,1219,4701,17939,71573,284089, 1157733,4721259,19569779,81402649,342160546, 1445001223,6145007988,26261712426,112789021222, 486638853729,2107738866605,9165837675101, 39988572047898,175057214787952,768550521307934, 3383830890482911,14937351793963389] |