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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 4 |
| 3 | 10 |
| 4 | 20 |
| 5 | 35 |
| 6 | 56 |
| 7 | 84 |
| 8 | 120 |
| 9 | 165 |
| 10 | 220 |
| 11 | 286 |
| 12 | 364 |
| 13 | 455 |
| 14 | 560 |
| 15 | 680 |
| 16 | 816 |
| 17 | 969 |
| 18 | 1140 |
| 19 | 1330 |
| 20 | 1540 |
| 21 | 1771 |
| 22 | 2024 |
| 23 | 2300 |
| 24 | 2600 |
| 25 | 2925 |
| 26 | 3276 |
| 27 | 3654 |
| 28 | 4060 |
| 29 | 4495 |
| 30 | 4960 |
| 31 | 5456 |
| 32 | 5984 |
| 33 | 6545 |
| 34 | 7140 |
| 35 | 7770 |
| 36 | 8436 |
| 37 | 9139 |
| 38 | 9880 |
| 39 | 10660 |
| 40 | 11480 |
| 41 | 12341 |
| 42 | 13244 |
| 43 | 14190 |
| 44 | 15180 |
[0,1,4,10,20,35,56,84,120,165,220,286,364,455,560, 680,816,969,1140,1330,1540,1771,2024,2300,2600, 2925,3276,3654,4060,4495,4960,5456,5984,6545,7140, 7770,8436,9139,9880,10660,11480,12341,13244,14190, 15180] |