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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 8 |
| 5 | 22 |
| 6 | 65 |
| 7 | 200 |
| 8 | 637 |
| 9 | 2090 |
| 10 | 7021 |
| 11 | 24041 |
| 12 | 83611 |
| 13 | 294511 |
| 14 | 1048376 |
| 15 | 3765080 |
| 16 | 13623820 |
| 17 | 49617990 |
| 18 | 181733222 |
| 19 | 668947823 |
| 20 | 2473277248 |
| 21 | 9180700787 |
| 22 | 34200489886 |
| 23 | 127819746470 |
| 24 | 479124333321 |
| 25 | 1800838945043 |
| 26 | 6785517883825 |
| 27 | 25626477179000 |
| 28 | 96988079848223 |
| 29 | 367794448974300 |
| 30 | 1397301289617580 |
[1,1,3,8,22,65,200,637,2090,7021,24041,83611, 294511,1048376,3765080,13623820,49617990, 181733222,668947823,2473277248,9180700787, 34200489886,127819746470,479124333321, 1800838945043,6785517883825,25626477179000, 96988079848223,367794448974300,1397301289617580] |