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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 65 |
| 5 | 253 |
| 6 | 1071 |
| 7 | 4469 |
| 8 | 18995 |
| 9 | 82111 |
| 10 | 359215 |
| 11 | 1581495 |
| 12 | 7010885 |
| 13 | 31284419 |
| 14 | 140356821 |
| 15 | 632723871 |
| 16 | 2863416051 |
| 17 | 13002311353 |
| 18 | 59240248483 |
| 19 | 270728014969 |
| 20 | 1240386485657 |
| 21 | 5695744333945 |
| 22 | 26211915574453 |
| 23 | 120875008483619 |
| 24 | 558420257834857 |
| 25 | 2583981455639041 |
| 26 | 11975292029692161 |
| 27 | 55580014426467833 |
[1,1,5,17,65,253,1071,4469,18995,82111,359215, 1581495,7010885,31284419,140356821,632723871, 2863416051,13002311353,59240248483,270728014969, 1240386485657,5695744333945,26211915574453, 120875008483619,558420257834857,2583981455639041, 11975292029692161,55580014426467833] |