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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 1 |
| 8 | 2 |
| 9 | 78 |
| 10 | 888 |
| 11 | 13909 |
| 12 | 204448 |
| 13 | 3182225 |
| 14 | 51504968 |
| 15 | 873224962 |
| 16 | 15498424578 |
| 17 | 287972983669 |
| 18 | 5598118158336 |
| 19 | 113756109812283 |
| 20 | 2413723031593090 |
| 21 | 53416658591208438 |
| 22 | 1231458960862452472 |
| 23 | 29538634475147637783 |
| 24 | 736321207493996695072 |
[1,0,0,0,0,0,0,1,2,78,888,13909,204448,3182225, 51504968,873224962,15498424578,287972983669, 5598118158336,113756109812283,2413723031593090, 53416658591208438,1231458960862452472, 29538634475147637783,736321207493996695072] |