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 A176140 Semiprimes s such that both s + 3 and s - 3 are primes. 0
 10, 14, 26, 34, 86, 106, 134, 194, 226, 254, 274, 314, 334, 386, 446, 566, 974, 1094, 1126, 1226, 1234, 1286, 1294, 1486, 1546, 1874, 2066, 2374, 2386, 2554, 2854, 2906, 2966, 3086, 3166, 3254, 3326, 3466, 3694, 4054, 4286, 4594, 4786, 4874, 4934, 4954 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS 2*5=10-+3->7,13 primes,... LINKS MATHEMATICA f[n_]:=Last/@FactorInteger[n]=={1, 1}; lst={}; Do[If[f[n]&&PrimeQ[n-3]&&PrimeQ[n+3], AppendTo[lst, n]], {n, 0, 4*7!}]; lst Select[Range[5000], PrimeOmega[#]==2&&AllTrue[#+{3, -3}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Nov 05 2017 *) CROSSREFS Cf. A125215, A125216 Sequence in context: A175664 A053690 A177948 * A031028 A176810 A115603 Adjacent sequences:  A176137 A176138 A176139 * A176141 A176142 A176143 KEYWORD nonn AUTHOR Vladimir Joseph Stephan Orlovsky, Apr 09 2010 EXTENSIONS Definition corrected by Zak Seidov, May 06 2013 STATUS approved

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Last modified October 15 05:43 EDT 2019. Contains 328026 sequences. (Running on oeis4.)