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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 13 |
| 4 | 30 |
| 5 | 56 |
| 6 | 127 |
| 7 | 243 |
| 8 | 508 |
| 9 | 999 |
| 10 | 2041 |
| 11 | 4038 |
| 12 | 8182 |
| 13 | 16265 |
| 14 | 32745 |
| 15 | 65302 |
| 16 | 131034 |
| 17 | 261669 |
| 18 | 524217 |
| 19 | 1047630 |
| 20 | 2097010 |
| 21 | 4192405 |
| 22 | 8388329 |
| 23 | 16773406 |
| 24 | 33553890 |
| 25 | 67101277 |
| 26 | 134216625 |
| 27 | 268420174 |
| 28 | 536868850 |
| 29 | 1073711381 |
| 30 | 2147479273 |
| 31 | 4294906222 |
| 32 | 8589926290 |
[1,2,6,13,30,56,127,243,508,999,2041,4038,8182, 16265,32745,65302,131034,261669,524217,1047630, 2097010,4192405,8388329,16773406,33553890, 67101277,134216625,268420174,536868850,1073711381, 2147479273,4294906222,8589926290] |