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A103296
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Number of complete rulers with n segments.
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4
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1, 1, 3, 10, 38, 175, 885, 5101, 32080, 219569, 1616882, 12747354, 106948772, 950494868
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OFFSET
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0,3
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COMMENTS
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For definitions, references and links related to complete rulers see A103294.
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LINKS
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FORMULA
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a(n) = Sum_{i=n..A004137(n+1)} T(i, n) where T is the A103294 triangle.
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EXAMPLE
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a(2)=3 counts the complete rulers with 2 segments, {[0,1,2],[0,1,3],[0,2,3]}.
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PROG
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Link to FORTRAN program given in A103295.
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CROSSREFS
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Cf. A103301 (perfect rulers with n segments), A103299 (optimal rulers with n segments).
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KEYWORD
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nonn,hard,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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