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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 17 |
| 6 | 71 |
| 7 | 359 |
| 8 | 2126 |
| 9 | 14495 |
| 10 | 111921 |
| 11 | 966709 |
| 12 | 9243208 |
| 13 | 96991006 |
| 14 | 1108710232 |
| 15 | 13719469288 |
| 16 | 182771488479 |
| 17 | 2608852914820 |
| 18 | 39730632184343 |
| 19 | 643142016659417 |
| 20 | 11029056364607167 |
| 21 | 199761704824369543 |
| 22 | 3811075717138755529 |
| 23 | 76396392619230455931 |
| 24 | 1605504868758470118493 |
[1,1,1,2,5,17,71,359,2126,14495,111921,966709, 9243208,96991006,1108710232,13719469288, 182771488479,2608852914820,39730632184343, 643142016659417,11029056364607167, 199761704824369543,3811075717138755529, 76396392619230455931,1605504868758470118493] |