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| n | a(n) |
|---|---|
| 0 | 10 |
| 1 | 56 |
| 2 | 242 |
| 3 | 988 |
| 4 | 3974 |
| 5 | 15920 |
| 6 | 63706 |
| 7 | 254852 |
| 8 | 1019438 |
| 9 | 4077784 |
| 10 | 16311170 |
| 11 | 65244716 |
| 12 | 260978902 |
| 13 | 1043915648 |
| 14 | 4175662634 |
| 15 | 16702650580 |
| 16 | 66810602366 |
| 17 | 267242409512 |
| 18 | 1068969638098 |
| 19 | 4275878552444 |
| 20 | 17103514209830 |
| 21 | 68414056839376 |
[10,56,242,988,3974,15920,63706,254852,1019438, 4077784,16311170,65244716,260978902,1043915648, 4175662634,16702650580,66810602366,267242409512, 1068969638098,4275878552444,17103514209830, 68414056839376] |