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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 17 |
| 6 | 5 |
| 7 | 17 |
| 8 | 61 |
| 9 | 559 |
| 10 | 269 |
| 11 | 5851 |
| 12 | 5279 |
| 13 | 954913 |
| 14 | 1693849 |
| 15 | 6394159 |
| 16 | 1430687 |
| 17 | 33257690117 |
| 18 | 393069739 |
| 19 | 330504317141 |
| 20 | 146861034421 |
| 21 | 3447587278559 |
| 22 | 13150098373 |
| 23 | 17185160160637123 |
| 24 | 68404253084009 |
| 25 | 219367146802450039 |
| 26 | 527431007100952693 |
| 27 | 2089195405327981487 |
[1,0,1,1,1,17,5,17,61,559,269,5851,5279,954913, 1693849,6394159,1430687,33257690117,393069739, 330504317141,146861034421,3447587278559, 13150098373,17185160160637123,68404253084009, 219367146802450039,527431007100952693, 2089195405327981487] |