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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 4 |
| 8 | 7 |
| 9 | 10 |
| 10 | 10 |
| 11 | 15 |
| 12 | 20 |
| 13 | 25 |
| 14 | 30 |
| 15 | 42 |
| 16 | 49 |
| 17 | 56 |
| 18 | 63 |
| 19 | 79 |
| 20 | 95 |
| 21 | 111 |
| 22 | 120 |
| 23 | 140 |
| 24 | 160 |
| 25 | 180 |
| 26 | 200 |
| 27 | 233 |
| 28 | 257 |
| 29 | 281 |
| 30 | 305 |
| 31 | 344 |
| 32 | 383 |
| 33 | 422 |
| 34 | 450 |
| 35 | 495 |
| 36 | 540 |
| 37 | 585 |
| 38 | 630 |
| 39 | 694 |
| 40 | 745 |
| 41 | 796 |
| 42 | 847 |
| 43 | 919 |
| 44 | 991 |
| 45 | 1063 |
| 46 | 1120 |
| 47 | 1200 |
| 48 | 1280 |
| 49 | 1360 |
| 50 | 1440 |
| 51 | 1545 |
| 52 | 1633 |
| 53 | 1721 |
| 54 | 1809 |
[0,0,0,1,1,1,1,4,7,10,10,15,20,25,30,42,49,56,63, 79,95,111,120,140,160,180,200,233,257,281,305,344, 383,422,450,495,540,585,630,694,745,796,847,919, 991,1063,1120,1200,1280,1360,1440,1545,1633,1721, 1809] |