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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 3 |
| 4 | 6 |
| 5 | 10 |
| 6 | 15 |
| 7 | 21 |
| 8 | 28 |
| 9 | 35 |
| 10 | 43 |
| 11 | 52 |
| 12 | 62 |
| 13 | 73 |
| 14 | 85 |
| 15 | 98 |
| 16 | 112 |
| 17 | 126 |
| 18 | 141 |
| 19 | 157 |
| 20 | 174 |
| 21 | 192 |
| 22 | 211 |
| 23 | 231 |
| 24 | 252 |
| 25 | 273 |
| 26 | 295 |
| 27 | 318 |
| 28 | 342 |
| 29 | 367 |
| 30 | 393 |
| 31 | 420 |
| 32 | 448 |
| 33 | 476 |
| 34 | 505 |
| 35 | 535 |
| 36 | 566 |
| 37 | 598 |
| 38 | 631 |
| 39 | 665 |
| 40 | 700 |
| 41 | 735 |
| 42 | 771 |
| 43 | 808 |
| 44 | 846 |
| 45 | 885 |
| 46 | 925 |
[0,0,1,3,6,10,15,21,28,35,43,52,62,73,85,98,112, 126,141,157,174,192,211,231,252,273,295,318,342, 367,393,420,448,476,505,535,566,598,631,665,700, 735,771,808,846,885,925] |