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| n | a(n) |
|---|---|
| -1 | 1 |
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 20 |
| 4 | 56 |
| 5 | 126 |
| 6 | 246 |
| 7 | 435 |
| 8 | 715 |
| 9 | 1111 |
| 10 | 1651 |
| 11 | 2366 |
| 12 | 3290 |
| 13 | 4460 |
| 14 | 5916 |
| 15 | 7701 |
| 16 | 9861 |
| 17 | 12445 |
| 18 | 15505 |
| 19 | 19096 |
| 20 | 23276 |
| 21 | 28106 |
| 22 | 33650 |
| 23 | 39975 |
| 24 | 47151 |
| 25 | 55251 |
| 26 | 64351 |
| 27 | 74530 |
| 28 | 85870 |
| 29 | 98456 |
| 30 | 112376 |
| 31 | 127721 |
| 32 | 144585 |
| 33 | 163065 |
| 34 | 183261 |
| 35 | 205276 |
| 36 | 229216 |
| 37 | 255190 |
| 38 | 283310 |
| 39 | 313691 |
[1,1,1,5,20,56,126,246,435,715,1111,1651,2366, 3290,4460,5916,7701,9861,12445,15505,19096,23276, 28106,33650,39975,47151,55251,64351,74530,85870, 98456,112376,127721,144585,163065,183261,205276, 229216,255190,283310,313691] |