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| n | a(n) |
|---|---|
| 3 | 0 |
| 4 | 1 |
| 5 | 7 |
| 6 | 39 |
| 7 | 209 |
| 8 | 1123 |
| 9 | 6153 |
| 10 | 34723 |
| 11 | 202852 |
| 12 | 1229672 |
| 13 | 7742792 |
| 14 | 50653678 |
| 15 | 344195782 |
| 16 | 2427812876 |
| 17 | 17761759538 |
| 18 | 134650690097 |
| 19 | 1056676856777 |
| 20 | 8574943334545 |
| 21 | 71881479393513 |
| 22 | 621792661601615 |
| 23 | 5544644720281979 |
| 24 | 50918125911279963 |
| 25 | 481093310682127190 |
[0,1,7,39,209,1123,6153,34723,202852,1229672, 7742792,50653678,344195782,2427812876,17761759538, 134650690097,1056676856777,8574943334545, 71881479393513,621792661601615,5544644720281979, 50918125911279963,481093310682127190] |