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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 9 |
| 4 | 28 |
| 5 | 100 |
| 6 | 198 |
| 7 | 441 |
| 8 | 720 |
| 9 | 1296 |
| 10 | 1900 |
| 11 | 3025 |
| 12 | 4140 |
| 13 | 6084 |
| 14 | 7938 |
| 15 | 11025 |
| 16 | 13888 |
| 17 | 18496 |
| 18 | 22680 |
| 19 | 29241 |
| 20 | 35100 |
| 21 | 44100 |
| 22 | 52030 |
| 23 | 64009 |
| 24 | 74448 |
| 25 | 90000 |
| 26 | 103428 |
| 27 | 123201 |
| 28 | 140140 |
| 29 | 164836 |
| 30 | 185850 |
| 31 | 216225 |
| 32 | 241920 |
| 33 | 278784 |
| 34 | 309808 |
| 35 | 354025 |
| 36 | 391068 |
| 37 | 443556 |
| 38 | 487350 |
| 39 | 549081 |
[0,0,9,28,100,198,441,720,1296,1900,3025,4140, 6084,7938,11025,13888,18496,22680,29241,35100, 44100,52030,64009,74448,90000,103428,123201, 140140,164836,185850,216225,241920,278784,309808, 354025,391068,443556,487350,549081] |