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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 0 |
| 9 | 7 |
| 10 | 8 |
| 11 | 9 |
| 12 | 27 |
| 13 | 30 |
| 14 | 33 |
| 15 | 121 |
| 16 | 138 |
| 17 | 156 |
| 18 | 520 |
| 19 | 595 |
| 20 | 675 |
| 21 | 2255 |
| 22 | 2600 |
| 23 | 2975 |
| 24 | 9877 |
| 25 | 11445 |
| 26 | 13167 |
| 27 | 43510 |
| 28 | 50625 |
| 29 | 58513 |
| 30 | 192801 |
| 31 | 225093 |
| 32 | 261165 |
| 33 | 858199 |
| 34 | 1004754 |
| 35 | 1169505 |
| 36 | 3834655 |
| 37 | 4500210 |
| 38 | 5252445 |
| 39 | 17189667 |
| 40 | 20214327 |
[0,0,0,0,0,0,0,0,7,8,9,27,30,33,121,138,156,520, 595,675,2255,2600,2975,9877,11445,13167,43510, 50625,58513,192801,225093,261165,858199,1004754, 1169505,3834655,4500210,5252445,17189667,20214327] |