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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 6 |
| 3 | 25 |
| 4 | 30 |
| 5 | 45 |
| 6 | 98 |
| 7 | 296 |
| 8 | 498 |
| 9 | 627 |
| 10 | 1001 |
| 11 | 1995 |
| 12 | 1998 |
| 13 | 2518 |
| 14 | 3208 |
| 15 | 3753 |
| 16 | 4130 |
| 17 | 7159 |
| 18 | 7660 |
| 19 | 10840 |
| 20 | 16187 |
| 21 | 24744 |
| 22 | 28345 |
| 23 | 31499 |
| 24 | 32999 |
| 25 | 44838 |
| 26 | 60959 |
| 27 | 88938 |
| 28 | 209846 |
[2,6,25,30,45,98,296,498,627,1001,1995,1998,2518, 3208,3753,4130,7159,7660,10840,16187,24744,28345, 31499,32999,44838,60959,88938,209846] |