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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 75 |
| 5 | 289 |
| 6 | 1321 |
| 7 | 5603 |
| 8 | 26151 |
| 9 | 115545 |
| 10 | 546467 |
| 11 | 2476781 |
| 12 | 11824411 |
| 13 | 54562395 |
| 14 | 262245791 |
| 15 | 1225932563 |
| 16 | 5921776307 |
| 17 | 27954464511 |
| 18 | 135555532109 |
| 19 | 644771630961 |
| 20 | 3136297717081 |
| 21 | 15007918416499 |
| 22 | 73187078083773 |
| 23 | 351930016225887 |
| 24 | 1719847828600187 |
| 25 | 8303424758407139 |
| 26 | 40650829603059627 |
| 27 | 196922384481104843 |
[1,1,5,17,75,289,1321,5603,26151,115545,546467, 2476781,11824411,54562395,262245791,1225932563, 5921776307,27954464511,135555532109,644771630961, 3136297717081,15007918416499,73187078083773, 351930016225887,1719847828600187,8303424758407139, 40650829603059627,196922384481104843] |