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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 41 |
| 5 | 160 |
| 6 | 641 |
| 7 | 2672 |
| 8 | 11479 |
| 9 | 50938 |
| 10 | 232830 |
| 11 | 1095151 |
| 12 | 5292990 |
| 13 | 26257328 |
| 14 | 133548307 |
| 15 | 695752146 |
| 16 | 3709509938 |
| 17 | 20224607541 |
| 18 | 112675185837 |
| 19 | 641016837378 |
| 20 | 3721624588590 |
| 21 | 22037618432547 |
| 22 | 133023405207408 |
| 23 | 818085097509494 |
| 24 | 5123460267381837 |
| 25 | 32660335570381961 |
| 26 | 211825198708110059 |
[1,3,11,41,160,641,2672,11479,50938,232830, 1095151,5292990,26257328,133548307,695752146, 3709509938,20224607541,112675185837,641016837378, 3721624588590,22037618432547,133023405207408, 818085097509494,5123460267381837, 32660335570381961,211825198708110059] |