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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 65 |
| 5 | 255 |
| 6 | 1051 |
| 7 | 4337 |
| 8 | 18319 |
| 9 | 77799 |
| 10 | 335201 |
| 11 | 1450767 |
| 12 | 6335303 |
| 13 | 27779333 |
| 14 | 122569423 |
| 15 | 542725045 |
| 16 | 2414192351 |
| 17 | 10771535425 |
| 18 | 48230144207 |
| 19 | 216516379107 |
| 20 | 974747732287 |
| 21 | 4398144695763 |
| 22 | 19891097561473 |
| 23 | 90135432973947 |
| 24 | 409245946151499 |
| 25 | 1861292534594845 |
| 26 | 8479599885242863 |
| 27 | 38689127745452473 |
[1,1,5,17,65,255,1051,4337,18319,77799,335201, 1450767,6335303,27779333,122569423,542725045, 2414192351,10771535425,48230144207,216516379107, 974747732287,4398144695763,19891097561473, 90135432973947,409245946151499,1861292534594845, 8479599885242863,38689127745452473] |