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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 11 |
| 3 | 29 |
| 4 | 109 |
| 5 | 287 |
| 6 | 1079 |
| 7 | 2841 |
| 8 | 10681 |
| 9 | 28123 |
| 10 | 105731 |
| 11 | 278389 |
| 12 | 1046629 |
| 13 | 2755767 |
| 14 | 10360559 |
| 15 | 27279281 |
| 16 | 102558961 |
| 17 | 270037043 |
| 18 | 1015229051 |
| 19 | 2673091149 |
| 20 | 10049731549 |
| 21 | 26460874447 |
| 22 | 99482086439 |
| 23 | 261935653321 |
| 24 | 984771132841 |
| 25 | 2592895658763 |
| 26 | 9748229241971 |
[1,3,11,29,109,287,1079,2841,10681,28123,105731, 278389,1046629,2755767,10360559,27279281, 102558961,270037043,1015229051,2673091149, 10049731549,26460874447,99482086439,261935653321, 984771132841,2592895658763,9748229241971] |