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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 15 |
| 3 | 51 |
| 4 | 210 |
| 5 | 330 |
| 6 | 651 |
| 7 | 1365 |
| 8 | 1650 |
| 9 | 1926 |
| 10 | 3480 |
| 11 | 5430 |
| 12 | 5985 |
| 13 | 6501 |
| 14 | 11310 |
| 15 | 16485 |
| 16 | 16590 |
| 17 | 21660 |
| 18 | 25026 |
| 19 | 27270 |
| 20 | 28635 |
| 21 | 35190 |
| 22 | 38001 |
| 23 | 39285 |
| 24 | 46905 |
| 25 | 48690 |
| 26 | 58905 |
| 27 | 64170 |
| 28 | 90651 |
| 29 | 109485 |
| 30 | 143376 |
| 31 | 148995 |
| 32 | 151845 |
| 33 | 190995 |
| 34 | 311676 |
| 35 | 316251 |
| 36 | 332526 |
[2,15,51,210,330,651,1365,1650,1926,3480,5430, 5985,6501,11310,16485,16590,21660,25026,27270, 28635,35190,38001,39285,46905,48690,58905,64170, 90651,109485,143376,148995,151845,190995,311676, 316251,332526] |