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A317402
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Number of distinct (up to rotation and reflection) tic-tac-toe positions with n tokens which allow a winning strategy for O.
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2
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OFFSET
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0,4
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COMMENTS
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Including positions where O has already won (that is, 0 for odd n and A048245(n) for even n).
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LINKS
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EXAMPLE
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a(4) = 5:
x x o x x o o x . o x . . x .
. . o . . . . . x . o . o o .
. . . . . o o . . . x . . x .
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CROSSREFS
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KEYWORD
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fini,full,nonn
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AUTHOR
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STATUS
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approved
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