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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 3 |
| 3 | 16 |
| 4 | 105 |
| 5 | 771 |
| 6 | 6083 |
| 7 | 50464 |
| 8 | 434493 |
| 9 | 3849715 |
| 10 | 34895685 |
| 11 | 322239204 |
| 12 | 3021922137 |
| 13 | 28710585099 |
| 14 | 275827551795 |
| 15 | 2675584398912 |
| 16 | 26173225402437 |
| 17 | 257940602058051 |
| 18 | 2558852771578817 |
| 19 | 25534696636443160 |
| 20 | 256164209036422239 |
| 21 | 2582189471692118101 |
| 22 | 26142642319644094293 |
[0,1,3,16,105,771,6083,50464,434493,3849715, 34895685,322239204,3021922137,28710585099, 275827551795,2675584398912,26173225402437, 257940602058051,2558852771578817, 25534696636443160,256164209036422239, 2582189471692118101,26142642319644094293] |