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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 13 |
| 4 | 28 |
| 5 | 56 |
| 6 | 123 |
| 7 | 243 |
| 8 | 496 |
| 9 | 993 |
| 10 | 2017 |
| 11 | 4033 |
| 12 | 8157 |
| 13 | 16285 |
| 14 | 32673 |
| 15 | 65305 |
| 16 | 130921 |
| 17 | 261729 |
| 18 | 523905 |
| 19 | 1047729 |
| 20 | 2096417 |
| 21 | 4192401 |
| 22 | 8387329 |
| 23 | 16774001 |
| 24 | 33551472 |
| 25 | 67100801 |
| 26 | 134213285 |
| 27 | 268422741 |
| 28 | 536860069 |
| 29 | 1073709657 |
| 30 | 2147466385 |
| 31 | 4294916961 |
| 32 | 8589891865 |
[1,2,6,13,28,56,123,243,496,993,2017,4033,8157, 16285,32673,65305,130921,261729,523905,1047729, 2096417,4192401,8387329,16774001,33551472, 67100801,134213285,268422741,536860069,1073709657, 2147466385,4294916961,8589891865] |