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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 7 |
| 3 | 25 |
| 4 | 65 |
| 5 | 140 |
| 6 | 266 |
| 7 | 462 |
| 8 | 750 |
| 9 | 1155 |
| 10 | 1705 |
| 11 | 2431 |
| 12 | 3367 |
| 13 | 4550 |
| 14 | 6020 |
| 15 | 7820 |
| 16 | 9996 |
| 17 | 12597 |
| 18 | 15675 |
| 19 | 19285 |
| 20 | 23485 |
| 21 | 28336 |
| 22 | 33902 |
| 23 | 40250 |
| 24 | 47450 |
| 25 | 55575 |
| 26 | 64701 |
| 27 | 74907 |
| 28 | 86275 |
| 29 | 98890 |
| 30 | 112840 |
| 31 | 128216 |
| 32 | 145112 |
| 33 | 163625 |
| 34 | 183855 |
| 35 | 205905 |
| 36 | 229881 |
| 37 | 255892 |
| 38 | 284050 |
| 39 | 314470 |
[0,1,7,25,65,140,266,462,750,1155,1705,2431,3367, 4550,6020,7820,9996,12597,15675,19285,23485,28336, 33902,40250,47450,55575,64701,74907,86275,98890, 112840,128216,145112,163625,183855,205905,229881, 255892,284050,314470] |