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A319236
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The profile of the backtrack tree for the sixteen queens problem.
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1
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1, 16, 210, 2236, 19688, 141812, 838816, 3998456, 15324708, 46358876, 108478966, 193892860, 260303408, 253897632, 171158018, 72002088, 14772512
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OFFSET
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0,2
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COMMENTS
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The profile (p_0, p_1, ..., p_n) is the number of nodes at each level of the tree.
The backtrack tree as defined by Knuth has for the sixteen queens problem 1141190303 nodes.
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REFERENCES
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D. E. Knuth, The Art of Computer Programming, Volume 4, Pre-fascicle 5B, Introduction to Backtracking, 7.2.2. Backtrack programming. 2018.
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LINKS
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FORMULA
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a(16) = A000170(16), the number of solutions.
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CROSSREFS
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KEYWORD
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nonn,fini,full
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AUTHOR
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STATUS
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approved
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