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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 4 |
| 7 | 16 |
| 8 | 25 |
| 9 | 36 |
| 10 | 144 |
| 11 | 324 |
| 12 | 1849 |
| 13 | 6400 |
| 14 | 23716 |
| 15 | 36481 |
| 16 | 51984 |
| 17 | 207936 |
| 18 | 467856 |
| 19 | 2666689 |
| 20 | 9229444 |
| 21 | 34199104 |
| 22 | 52606009 |
| 23 | 74960964 |
| 24 | 299843856 |
| 25 | 674648676 |
| 26 | 3845364121 |
| 27 | 13308852496 |
| 28 | 49315084900 |
| 29 | 75857828929 |
| 30 | 108093658176 |
| 31 | 432374632704 |
| 32 | 972842923584 |
| 33 | 5545012396225 |
| 34 | 19191356070436 |
| 35 | 71112318227344 |
| 36 | 109386936710041 |
| 37 | 155870980128900 |
| 38 | 623483920515600 |
| 39 | 1402838821160100 |
[0,0,0,0,1,4,16,25,36,144,324,1849,6400,23716, 36481,51984,207936,467856,2666689,9229444, 34199104,52606009,74960964,299843856,674648676, 3845364121,13308852496,49315084900,75857828929, 108093658176,432374632704,972842923584, 5545012396225,19191356070436,71112318227344, 109386936710041,155870980128900,623483920515600, 1402838821160100] |