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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 11 |
| 3 | 33 |
| 4 | 98 |
| 5 | 291 |
| 6 | 865 |
| 7 | 2570 |
| 8 | 7637 |
| 9 | 22693 |
| 10 | 67432 |
| 11 | 200373 |
| 12 | 595405 |
| 13 | 1769236 |
| 14 | 5257255 |
| 15 | 15621845 |
| 16 | 46420050 |
| 17 | 137936399 |
| 18 | 409875693 |
| 19 | 1217938738 |
| 20 | 3619084505 |
| 21 | 10754048825 |
| 22 | 31955475472 |
| 23 | 94955158681 |
| 24 | 282157659273 |
| 25 | 838426745764 |
| 26 | 2491370993875 |
[4,11,33,98,291,865,2570,7637,22693,67432,200373, 595405,1769236,5257255,15621845,46420050, 137936399,409875693,1217938738,3619084505, 10754048825,31955475472,94955158681,282157659273, 838426745764,2491370993875] |