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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 15 |
| 4 | 6 |
| 5 | 105 |
| 6 | 30 |
| 7 | 1155 |
| 8 | 770 |
| 9 | 36465 |
| 10 | 210 |
| 11 | 15015 |
| 12 | 6006 |
| 13 | 255255 |
| 14 | 2310 |
| 15 | 8580495 |
| 16 | 102102 |
| 17 | 4849845 |
| 18 | 72930 |
| 19 | 20056049013 |
| 20 | 74364290 |
| 21 | 5898837945 |
| 22 | 30030 |
| 23 | 3234846615 |
| 24 | 881790 |
| 25 | 195282582495 |
| 26 | 510510 |
| 27 | 218257003965 |
| 28 | 20281170 |
| 29 | 100280245065 |
| 30 | 17160990 |
| 31 | 934482952262145 |
| 32 | 6614136163635 |
[1,2,15,6,105,30,1155,770,36465,210,15015,6006, 255255,2310,8580495,102102,4849845,72930, 20056049013,74364290,5898837945,30030,3234846615, 881790,195282582495,510510,218257003965,20281170, 100280245065,17160990,934482952262145, 6614136163635] |