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A271907
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Size of the largest subset S of the points of an n X n square grid such that no three of the points of S form an isosceles triangle.
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3
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OFFSET
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1,2
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COMMENTS
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S must not contain 3 points A,B,C such that |AB| = |BC|.
For example, this configuration is forbidden:
O O O B
O O O O
A O O O
O C O O
It appears that this is simply a(n) = 2n-2 for n>1, and if so this entry may be replaced by a comment in A271914 and A271906, and this A-number recycled.
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LINKS
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EXAMPLE
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Illustration for a(3) = 4:
O X X
X O O
X O O
Illustration for a(8) = 14:
O X X X X X O X
X O O O O O O X
X O O O O O O O
X O O O O O O O
X O O O O O O O
X O O O O O O O
O O O O O O O O
X X O O O O O O
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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