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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 7 |
| 4 | 8 |
| 5 | 77 |
| 6 | 192 |
| 7 | 1043 |
| 8 | 3472 |
| 9 | 15529 |
| 10 | 57792 |
| 11 | 240655 |
| 12 | 934808 |
| 13 | 3789653 |
| 14 | 14963328 |
| 15 | 60048443 |
| 16 | 238578976 |
| 17 | 953755537 |
| 18 | 3798340224 |
| 19 | 15162325975 |
| 20 | 60438310184 |
| 21 | 241126038941 |
| 22 | 961476161856 |
| 23 | 3835121918243 |
| 24 | 15294304429744 |
| 25 | 61000836720313 |
| 26 | 243280700771904 |
[1,0,7,8,77,192,1043,3472,15529,57792,240655, 934808,3789653,14963328,60048443,238578976, 953755537,3798340224,15162325975,60438310184, 241126038941,961476161856,3835121918243, 15294304429744,61000836720313,243280700771904] |