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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 19 |
| 5 | 30 |
| 6 | 120 |
| 7 | 170 |
| 8 | 647 |
| 9 | 1183 |
| 10 | 3650 |
| 11 | 5742 |
| 12 | 24916 |
| 13 | 33462 |
| 14 | 121652 |
| 15 | 240756 |
| 16 | 746639 |
| 17 | 1136690 |
| 18 | 4707147 |
| 19 | 6625110 |
| 20 | 25882770 |
| 21 | 46565244 |
| 22 | 139849776 |
| 23 | 225058682 |
| 24 | 978088748 |
| 25 | 1356970471 |
| 26 | 4750318586 |
| 27 | 9182205852 |
| 28 | 29333908544 |
| 29 | 44560482150 |
| 30 | 188175715440 |
| 31 | 259717522850 |
| 32 | 994309609247 |
[1,3,6,19,30,120,170,647,1183,3650,5742,24916, 33462,121652,240756,746639,1136690,4707147, 6625110,25882770,46565244,139849776,225058682, 978088748,1356970471,4750318586,9182205852, 29333908544,44560482150,188175715440,259717522850, 994309609247] |