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A088710
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Numbers n which are a product of two primes j and k such that n-j-k is prime.
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2
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9, 10, 14, 15, 21, 26, 33, 35, 38, 39, 51, 62, 65, 69, 77, 86, 91, 93, 95, 111, 122, 123, 129, 133, 146, 159, 161, 201, 203, 206, 209, 213, 215, 217, 218, 221, 249, 278, 287, 291, 299, 301, 302, 303, 305, 321, 335, 339, 362, 371, 381, 386, 395, 398, 403, 407
(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=3 which is prime.
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MATHEMATICA
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ptpQ[n_]:=PrimeOmega[n]==2&&PrimeQ[n-Total[Flatten[Table[#[[1]], #[[2]]]&/@ FactorInteger[n]]]]; Select[Range[500], ptpQ] (* Harvey P. Dale, Jun 04 2018 *)
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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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