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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 11 |
| 4 | 53 |
| 5 | 149 |
| 6 | 737 |
| 7 | 2351 |
| 8 | 11629 |
| 9 | 39687 |
| 10 | 197311 |
| 11 | 707205 |
| 12 | 3519205 |
| 13 | 13028739 |
| 14 | 64938435 |
| 15 | 246751393 |
| 16 | 1230673099 |
| 17 | 4768324351 |
| 18 | 23797616719 |
| 19 | 93712372299 |
| 20 | 467883669379 |
| 21 | 1866845588443 |
| 22 | 9323722318663 |
| 23 | 37619266504719 |
| 24 | 187928984011715 |
| 25 | 765483964644861 |
| 26 | 3824704802081289 |
| 27 | 15707739542521241 |
[1,1,5,11,53,149,737,2351,11629,39687,197311, 707205,3519205,13028739,64938435,246751393, 1230673099,4768324351,23797616719,93712372299, 467883669379,1866845588443,9323722318663, 37619266504719,187928984011715,765483964644861, 3824704802081289,15707739542521241] |