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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 15 |
| 4 | 35 |
| 5 | 70 |
| 6 | 127 |
| 7 | 215 |
| 8 | 345 |
| 9 | 530 |
| 10 | 785 |
| 11 | 1127 |
| 12 | 1575 |
| 13 | 2150 |
| 14 | 2875 |
| 15 | 3775 |
| 16 | 4877 |
| 17 | 6210 |
| 18 | 7805 |
| 19 | 9695 |
| 20 | 11915 |
| 21 | 14502 |
| 22 | 17495 |
| 23 | 20935 |
| 24 | 24865 |
| 25 | 29330 |
| 26 | 34377 |
| 27 | 40055 |
| 28 | 46415 |
| 29 | 53510 |
| 30 | 61395 |
| 31 | 70127 |
| 32 | 79765 |
| 33 | 90370 |
| 34 | 102005 |
| 35 | 114735 |
| 36 | 128627 |
| 37 | 143750 |
| 38 | 160175 |
| 39 | 177975 |
[1,5,15,35,70,127,215,345,530,785,1127,1575,2150, 2875,3775,4877,6210,7805,9695,11915,14502,17495, 20935,24865,29330,34377,40055,46415,53510,61395, 70127,79765,90370,102005,114735,128627,143750, 160175,177975] |