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A064900
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Semiprimes p1*p2 such that p2 > p1 and p2 mod p1 = 2.
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4
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15, 33, 35, 51, 69, 85, 87, 123, 141, 143, 159, 161, 177, 185, 213, 235, 249, 259, 267, 303, 321, 323, 335, 339, 393, 411, 447, 485, 501, 519, 533, 535, 537, 553, 573, 591, 635, 681, 685, 699, 717, 749, 753, 771, 785, 789, 807, 835, 843, 869, 871, 879, 899
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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okQ[n_] := Module[{p, e}, {p, e} = Transpose[FactorInteger[n]]; e == {1, 1} && Mod[p[[2]], p[[1]]] == 2]; Select[Range[1000], okQ]
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PROG
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(PARI) isok(n) = (bigomega(n)==2) && (f=factor(n)) && (#f~ == 2) && ((f[2, 1] % f[1, 1]) == 2); \\ Michel Marcus, May 20 2017
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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