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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 70 |
| 5 | 99 |
| 6 | 195 |
| 7 | 240 |
| 8 | 323 |
| 9 | 2378 |
| 10 | 2716 |
| 11 | 15015 |
| 12 | 48505 |
| 13 | 80782 |
| 14 | 130662 |
| 15 | 510068 |
| 16 | 672210 |
| 17 | 1926615 |
| 18 | 2744210 |
| 19 | 4116315 |
| 20 | 10278759 |
| 21 | 31320850 |
| 22 | 87347695 |
| 23 | 93222358 |
| 24 | 155904960 |
| 25 | 177385520 |
| 26 | 189539896 |
| 27 | 250637778 |
| 28 | 272607725 |
| 29 | 486471832 |
| 30 | 647562465 |
| 31 | 1620820270 |
[1,2,5,70,99,195,240,323,2378,2716,15015,48505, 80782,130662,510068,672210,1926615,2744210, 4116315,10278759,31320850,87347695,93222358, 155904960,177385520,189539896,250637778,272607725, 486471832,647562465,1620820270] |