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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 6 |
| 2 | 20 |
| 3 | 49 |
| 4 | 105 |
| 5 | 190 |
| 6 | 320 |
| 7 | 501 |
| 8 | 727 |
| 9 | 1026 |
| 10 | 1408 |
| 11 | 1853 |
| 12 | 2391 |
| 13 | 3026 |
| 14 | 3734 |
| 15 | 4579 |
| 16 | 5541 |
| 17 | 6620 |
| 18 | 7838 |
| 19 | 9201 |
| 20 | 10657 |
| 21 | 12328 |
| 22 | 14136 |
| 23 | 16123 |
| 24 | 18293 |
| 25 | 20658 |
| 26 | 23128 |
| 27 | 25905 |
| 28 | 28825 |
| 29 | 31994 |
| 30 | 35388 |
| 31 | 39029 |
| 32 | 42779 |
| 33 | 46942 |
| 34 | 51240 |
| 35 | 55865 |
| 36 | 60755 |
| 37 | 65946 |
| 38 | 71242 |
| 39 | 77071 |
| 40 | 83013 |
| 41 | 89368 |
| 42 | 96026 |
[1,6,20,49,105,190,320,501,727,1026,1408,1853, 2391,3026,3734,4579,5541,6620,7838,9201,10657, 12328,14136,16123,18293,20658,23128,25905,28825, 31994,35388,39029,42779,46942,51240,55865,60755, 65946,71242,77071,83013,89368,96026] |