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A295774
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a(n) is the minimum size of a restricted planar additive basis for the square [0,2n]^2.
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1
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1, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 60, 64, 68, 72, 76, 80, 84, 88, 92
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OFFSET
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0,2
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COMMENTS
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A planar additive basis for the square [0,2n]^2 is a set of points with nonnegative integer coordinates such that their pairwise sums cover the square. Self-sums are allowed. In a restricted basis all points are in the lower left quadrant [0,n]^2.
Matches A008574 at least up to a(23)=92.
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LINKS
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EXAMPLE
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a(2)=8: the square [0,4]^2 is covered by the pairwise sums of {(0,0),(1,0),(2,0),(0,1),(2,1),(0,2),(1,2),(2,2)}, which has 8 elements.
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CROSSREFS
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A295771 is the nonrestricted version.
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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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