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A083574
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Triangle: rows list the factors of composite odd n.
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0
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3, 3, 3, 5, 3, 7, 5, 5, 3, 3, 3, 3, 11, 5, 7, 3, 13, 3, 3, 5, 7, 7, 3, 17, 5, 11, 3, 19, 3, 3, 7, 5, 13, 3, 23, 3, 5, 5, 7, 11, 3, 3, 3, 3, 5, 17, 3, 29, 7, 13, 3, 31, 5, 19, 3, 3, 11, 3, 5, 7, 3, 37, 5, 23, 3, 3, 13, 7, 17, 11, 11, 3, 41, 5, 5, 5, 3, 43, 7
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OFFSET
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1,1
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COMMENTS
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The primes make their first appearance according to their distribution after p=7.
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LINKS
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EXAMPLE
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The first odd composites are 9,15,21, with factors 3.3,3.5,3.7, so the sequence opens 3,3,3,5,3,7
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MATHEMATICA
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fcon[n_]:=Table[#[[1]], #[[2]]]&/@FactorInteger[n]; fcon/@Select[ Range[ 9, 151, 2], CompositeQ]//Flatten (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Aug 20 2020 *)
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CROSSREFS
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KEYWORD
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nonn,tabf
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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