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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 4 |
| 3 | 9 |
| 4 | 20 |
| 5 | 35 |
| 6 | 66 |
| 7 | 105 |
| 8 | 176 |
| 9 | 270 |
| 10 | 420 |
| 11 | 616 |
| 12 | 924 |
| 13 | 1313 |
| 14 | 1890 |
| 15 | 2640 |
| 16 | 3696 |
| 17 | 5049 |
| 18 | 6930 |
| 19 | 9310 |
| 20 | 12540 |
| 21 | 16632 |
| 22 | 22044 |
| 23 | 28865 |
| 24 | 37800 |
| 25 | 48950 |
| 26 | 63336 |
| 27 | 81270 |
| 28 | 104104 |
| 29 | 132385 |
| 30 | 168120 |
| 31 | 212102 |
| 32 | 267168 |
| 33 | 334719 |
| 34 | 418540 |
| 35 | 520905 |
| 36 | 647172 |
| 37 | 800569 |
| 38 | 988570 |
| 39 | 1216215 |
| 40 | 1493520 |
[0,1,4,9,20,35,66,105,176,270,420,616,924,1313, 1890,2640,3696,5049,6930,9310,12540,16632,22044, 28865,37800,48950,63336,81270,104104,132385, 168120,212102,267168,334719,418540,520905,647172, 800569,988570,1216215,1493520] |