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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 83 |
| 5 | 333 |
| 6 | 1643 |
| 7 | 7155 |
| 8 | 35489 |
| 9 | 161173 |
| 10 | 801969 |
| 11 | 3736501 |
| 12 | 18625587 |
| 13 | 88230789 |
| 14 | 440281431 |
| 15 | 2109661555 |
| 16 | 10534432565 |
| 17 | 50894814307 |
| 18 | 254247117363 |
| 19 | 1235902365797 |
| 20 | 6175716789891 |
| 21 | 30161603582603 |
| 22 | 150743420895283 |
| 23 | 738923672434885 |
| 24 | 3693502675312573 |
| 25 | 18158046286023841 |
| 26 | 90770725819503389 |
[1,1,5,17,83,333,1643,7155,35489,161173,801969, 3736501,18625587,88230789,440281431,2109661555, 10534432565,50894814307,254247117363, 1235902365797,6175716789891,30161603582603, 150743420895283,738923672434885,3693502675312573, 18158046286023841,90770725819503389] |