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A241013
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Semiprimes congruent to {1, 2, 4} mod 5.
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1
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4, 6, 9, 14, 21, 22, 26, 34, 39, 46, 49, 51, 57, 62, 69, 74, 77, 82, 86, 87, 91, 94, 106, 111, 119, 121, 122, 129, 134, 141, 142, 146, 159, 161, 166, 169, 177, 187, 194, 201, 202, 206, 209, 214, 217, 219, 221, 226, 237, 247, 249, 254, 259, 262, 267, 274, 287, 289
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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21 = 3 * 7 which is semiprime and 21 = 1 mod 5.
39 = 3 * 13 which is semiprime and 39 = 4 mod 5.
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MATHEMATICA
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Select[Range[500], PrimeOmega[#] == 2 && MemberQ[{1, 2, 4}, Mod[#, 5]] &](* Bajpai *)
Select[Complement[Range[100], 5Range[20] - 2, 5Range[20]], PrimeOmega[#] == 2 &] (* Alonso del Arte, Aug 07 2014 *)
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PROG
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(PARI)
for(n=1, 10^4, if(n!=Mod(0, 5)&&n!=Mod(3, 5), if(bigomega(n)==2, print1(n, ", ")))) \\ Derek Orr, Aug 07 2014
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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