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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 42 |
| 5 | 155 |
| 6 | 511 |
| 7 | 2023 |
| 8 | 7760 |
| 9 | 31395 |
| 10 | 127575 |
| 11 | 526459 |
| 12 | 2194344 |
| 13 | 9206121 |
| 14 | 38933281 |
| 15 | 165380299 |
| 16 | 706470350 |
| 17 | 3028761985 |
| 18 | 13037475319 |
| 19 | 56289258695 |
| 20 | 243772244956 |
| 21 | 1058354286379 |
| 22 | 4606025822849 |
| 23 | 20087808189187 |
| 24 | 87780004451864 |
[1,5,17,42,155,511,2023,7760,31395,127575,526459, 2194344,9206121,38933281,165380299,706470350, 3028761985,13037475319,56289258695,243772244956, 1058354286379,4606025822849,20087808189187, 87780004451864] |