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A348161
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Number of factorizations of (n,n) into one or two pairs (i,j) with i > 0, j > 0 (and if i=1 then j=1).
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1
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1, 1, 1, 3, 1, 5, 1, 5, 3, 5, 1, 13, 1, 5, 5, 9, 1, 13, 1, 13, 5, 5, 1, 25, 3, 5, 5, 13, 1, 25, 1, 13, 5, 5, 5, 33, 1, 5, 5, 25, 1, 25, 1, 13, 13, 5, 1, 41, 3, 13, 5, 13, 1, 25, 5, 25, 5, 5, 1, 61, 1, 5, 13, 19, 5, 25, 1, 13, 5, 25, 1, 61, 1, 5, 13, 13, 5, 25
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OFFSET
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1,4
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LINKS
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FORMULA
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For n > 1, a(n) = ceiling((tau(n)-2)*tau(n)/2) + 1, where tau(n) = A000005(n).
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EXAMPLE
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(4,4) = (2,4)*(2,1) = (2,2)*(2,2), so a(4)=3.
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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