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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 32 |
| 5 | 107 |
| 6 | 406 |
| 7 | 1515 |
| 8 | 6056 |
| 9 | 23845 |
| 10 | 98122 |
| 11 | 399886 |
| 12 | 1682244 |
| 13 | 7032741 |
| 14 | 30086609 |
| 15 | 128154473 |
| 16 | 555416535 |
| 17 | 2399938654 |
| 18 | 10510610675 |
| 19 | 45938255055 |
| 20 | 202930811756 |
| 21 | 895234875377 |
| 22 | 3983322302128 |
| 23 | 17708513875474 |
| 24 | 79278341528189 |
| 25 | 354740946237274 |
| 26 | 1596531973524495 |
| 27 | 7183617499670049 |
| 28 | 32479226629073443 |
[1,1,3,9,32,107,406,1515,6056,23845,98122,399886, 1682244,7032741,30086609,128154473,555416535, 2399938654,10510610675,45938255055,202930811756, 895234875377,3983322302128,17708513875474, 79278341528189,354740946237274,1596531973524495, 7183617499670049,32479226629073443] |