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A285995
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Number of arrangements of n circles in the affine plane such that at least two of the circles meet.
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1
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OFFSET
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0,4
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COMMENTS
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A subset the arrangements of n circles described in A250001, which is the main entry for this sequence.
See also the comments related to A000081 from Benoit Jubin and N. J. A. Sloane in A250001.
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LINKS
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FORMULA
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CROSSREFS
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Row sums of A261070 except its column k = 0.
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KEYWORD
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nonn,bref,hard,more
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AUTHOR
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STATUS
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approved
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