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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 12 |
| 5 | 56 |
| 6 | 289 |
| 7 | 1604 |
| 8 | 9415 |
| 9 | 57801 |
| 10 | 368269 |
| 11 | 2421115 |
| 12 | 16352401 |
| 13 | 113075441 |
| 14 | 798316997 |
| 15 | 5741446395 |
| 16 | 41984708298 |
| 17 | 311673028845 |
| 18 | 2345644392051 |
| 19 | 17876342623580 |
| 20 | 137820598360123 |
| 21 | 1073961913716521 |
| 22 | 8452182814380104 |
| 23 | 67136452766364121 |
| 24 | 537890721293399309 |
[1,1,3,12,56,289,1604,9415,57801,368269,2421115, 16352401,113075441,798316997,5741446395, 41984708298,311673028845,2345644392051, 17876342623580,137820598360123,1073961913716521, 8452182814380104,67136452766364121, 537890721293399309] |