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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 5 |
| 7 | 33 |
| 8 | 245 |
| 9 | 2053 |
| 10 | 19137 |
| 11 | 196705 |
| 12 | 2212037 |
| 13 | 27029085 |
| 14 | 356723177 |
| 15 | 5058388153 |
| 16 | 76712450925 |
| 17 | 1239124984693 |
| 18 | 21241164552785 |
| 19 | 385159565775633 |
| 20 | 7365975246680597 |
| 21 | 148182892455224845 |
| 22 | 3128251523599365177 |
| 23 | 69149857480654157545 |
| 24 | 1597343462243140957757 |
[0,0,0,0,1,5,33,245,2053,19137,196705,2212037, 27029085,356723177,5058388153,76712450925, 1239124984693,21241164552785,385159565775633, 7365975246680597,148182892455224845, 3128251523599365177,69149857480654157545, 1597343462243140957757] |