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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 1 |
| 3 | 2 |
| 4 | 0 |
| 5 | 0 |
| 6 | 8 |
| 7 | 0 |
| 8 | 80 |
| 9 | 728 |
| 10 | 224 |
| 11 | 323 |
| 12 | 39168 |
| 13 | 82943 |
| 14 | 176399 |
| 15 | 215295 |
| 16 | 3444735 |
| 17 | 26167683 |
| 18 | 114349224 |
| 19 | 255004928 |
| 20 | 1158920360 |
| 21 | 11638526760 |
| 22 | 42128246888 |
| 23 | 191052974115 |
| 24 | 97216010328 |
| 25 | 2430400258224 |
| 26 | 1553580508515 |
| 27 | 4666092737475 |
[2,1,2,0,0,8,0,80,728,224,323,39168,82943,176399, 215295,3444735,26167683,114349224,255004928, 1158920360,11638526760,42128246888,191052974115, 97216010328,2430400258224,1553580508515, 4666092737475] |