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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 4 |
| 5 | 13 |
| 6 | 31 |
| 7 | 61 |
| 8 | 124 |
| 9 | 295 |
| 10 | 757 |
| 11 | 1873 |
| 12 | 4402 |
| 13 | 10237 |
| 14 | 24421 |
| 15 | 59701 |
| 16 | 146455 |
| 17 | 356308 |
| 18 | 862810 |
| 19 | 2096632 |
| 20 | 5127391 |
| 21 | 12583513 |
| 22 | 30886735 |
| 23 | 75775729 |
| 24 | 186054142 |
| 25 | 457662265 |
| 26 | 1127659903 |
| 27 | 2781162079 |
| 28 | 6862930768 |
| 29 | 16945704721 |
| 30 | 41876228125 |
| 31 | 103573882633 |
| 32 | 256359901387 |
| 33 | 634900971064 |
[1,1,1,1,4,13,31,61,124,295,757,1873,4402,10237, 24421,59701,146455,356308,862810,2096632,5127391, 12583513,30886735,75775729,186054142,457662265, 1127659903,2781162079,6862930768,16945704721, 41876228125,103573882633,256359901387, 634900971064] |