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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 5 |
| 4 | 5 |
| 5 | 5 |
| 6 | 30 |
| 7 | 55 |
| 8 | 80 |
| 9 | 230 |
| 10 | 530 |
| 11 | 1080 |
| 12 | 2505 |
| 13 | 5555 |
| 14 | 15130 |
| 15 | 34705 |
| 16 | 80530 |
| 17 | 197855 |
| 18 | 511455 |
| 19 | 1249430 |
| 20 | 2966155 |
| 21 | 7334380 |
| 22 | 18923630 |
| 23 | 46926130 |
| 24 | 114708755 |
| 25 | 287150005 |
| 26 | 741017280 |
| 27 | 1860971930 |
| 28 | 4628582080 |
| 29 | 11629943105 |
| 30 | 30291303280 |
| 31 | 76640090080 |
| 32 | 192409197255 |
[1,1,5,5,5,30,55,80,230,530,1080,2505,5555,15130, 34705,80530,197855,511455,1249430,2966155,7334380, 18923630,46926130,114708755,287150005,741017280, 1860971930,4628582080,11629943105,30291303280, 76640090080,192409197255] |