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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 1 |
| 9 | 1 |
| 10 | 1 |
| 11 | 2 |
| 12 | 21 |
| 13 | 105 |
| 14 | 316 |
| 15 | 705 |
| 16 | 1297 |
| 17 | 2181 |
| 18 | 3837 |
| 19 | 7596 |
| 20 | 15962 |
| 21 | 32998 |
| 22 | 66173 |
| 23 | 131379 |
| 24 | 261910 |
| 25 | 524012 |
| 26 | 1048568 |
| 27 | 2097228 |
| 28 | 4194318 |
| 29 | 8388600 |
| 30 | 16777216 |
| 31 | 33554434 |
| 32 | 67108864 |
| 33 | 134217728 |
| 34 | 268435456 |
| 35 | 536870912 |
| 36 | 1073741824 |
[1,1,1,1,1,1,1,1,1,1,1,2,21,105,316,705,1297,2181, 3837,7596,15962,32998,66173,131379,261910,524012, 1048568,2097228,4194318,8388600,16777216,33554434, 67108864,134217728,268435456,536870912,1073741824] |