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A088709
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Numbers m that are a product of two primes j and k such that m+j+k is prime.
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4
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6, 10, 14, 15, 21, 26, 33, 34, 35, 38, 46, 51, 55, 57, 58, 65, 74, 85, 86, 93, 111, 118, 123, 141, 143, 145, 155, 158, 161, 166, 177, 178, 185, 194, 201, 203, 205, 206, 209, 215, 221, 254, 267, 278, 295, 298, 319, 321, 323, 326, 327, 329, 334, 341, 346, 355, 365
(list;
graph;
refs;
listen;
history;
text;
internal format)
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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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a(2)=10 because 10 has only one pair of prime factors (2 and 5) and 10 + 2 + 5 = 17, which is prime.
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MATHEMATICA
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ptpQ[n_]:=Module[{fi=FactorInteger[n]}, Length[fi]==2&&Union[ fi[[All, 2]]] == {1}&&PrimeQ[n+Total[fi[[All, 1]]]]]; Select[Range[400], ptpQ] (* Harvey P. Dale, Nov 06 2020 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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Chuck Seggelin (barkeep(AT)plastereddragon.com), Oct 11 2003
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STATUS
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approved
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