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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 2 |
| 3 | 5 |
| 4 | 26 |
| 5 | 100 |
| 6 | 418 |
| 7 | 1692 |
| 8 | 6932 |
| 9 | 28288 |
| 10 | 115604 |
| 11 | 472188 |
| 12 | 1929012 |
| 13 | 7880012 |
| 14 | 32190588 |
| 15 | 131500508 |
| 16 | 537189116 |
| 17 | 2194454252 |
| 18 | 8964498844 |
| 19 | 36620598988 |
| 20 | 149597691420 |
| 21 | 611116954220 |
| 22 | 2496455194876 |
| 23 | 10198192807820 |
| 24 | 41660325742812 |
[0,2,5,26,100,418,1692,6932,28288,115604,472188, 1929012,7880012,32190588,131500508,537189116, 2194454252,8964498844,36620598988,149597691420, 611116954220,2496455194876,10198192807820, 41660325742812] |