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A052054
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Composite numbers all of whose prime factors (considered with multiplicity) share at least one digit.
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1
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4, 8, 9, 16, 25, 27, 32, 39, 46, 49, 58, 64, 69, 81, 92, 93, 111, 116, 117, 119, 121, 125, 128, 129, 143, 159, 169, 184, 187, 207, 209, 219, 221, 232, 243, 247, 249, 254, 256, 259, 265, 279, 289, 295, 299, 309, 323, 329, 333, 339, 341, 343, 351, 361, 368, 387
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OFFSET
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1,1
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LINKS
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EXAMPLE
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E.g., 92 = 2 * 2 * 23 is a term because the sets {2}, {2} and {2,3} share the digit 2.
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MATHEMATICA
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Select[2~Range~500, !PrimeQ@#&&And@@IntersectingQ@@@Subsets[ IntegerDigits[ First/@FactorInteger[#]], {2}]&] (* Giorgos Kalogeropoulos, May 09 2019 *)
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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