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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 42 |
| 5 | 163 |
| 6 | 639 |
| 7 | 2520 |
| 8 | 9976 |
| 9 | 39595 |
| 10 | 157441 |
| 11 | 626859 |
| 12 | 2498318 |
| 13 | 9964308 |
| 14 | 39764292 |
| 15 | 158756360 |
| 16 | 634044576 |
| 17 | 2532959099 |
| 18 | 10121210373 |
| 19 | 40449588625 |
| 20 | 161680869046 |
| 21 | 646330342699 |
| 22 | 2584001013295 |
| 23 | 10331554755044 |
| 24 | 41311180250504 |
[1,3,11,42,163,639,2520,9976,39595,157441,626859, 2498318,9964308,39764292,158756360,634044576, 2532959099,10121210373,40449588625,161680869046, 646330342699,2584001013295,10331554755044, 41311180250504] |