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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 7 |
| 6 | 28 |
| 7 | 171 |
| 8 | 2624 |
| 9 | 172613 |
| 10 | 139584150 |
| 11 | 6837485347187 |
| 12 | 266437138079023501057 |
| 13 | 508009471379222384299345337895696 |
| 14 | 37745517525533091954228691786161750063795478326636142 |
| 15 | 5347426383812697233786139576220412396732847744407175515852823296919414647252347610750 |
[1,1,1,1,3,7,28,171,2624,172613,139584150, 6837485347187,266437138079023501057, 508009471379222384299345337895696, 37745517525533091954228691786161750063795478326636\ 142, 53474263838126972337861395762204123967328477444071\ 75515852823296919414647252347610750] |