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 A157355 Products of 3 distinct not safe primes. 2
 78, 102, 114, 174, 186, 222, 246, 258, 318, 366, 402, 426, 438, 442, 474, 494, 534, 582, 606, 618, 646, 654, 663, 678, 741, 754, 762, 786, 806, 822, 834, 894, 906, 942, 962, 969, 978, 986, 1038, 1054, 1066, 1086, 1102, 1118, 1131, 1146, 1158, 1178, 1182 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS 78=2*3*13; 2,3 and 13 are not safe prime numbers,... LINKS Table of n, a(n) for n=1..49. MATHEMATICA lst={}; Do[If[Plus@@Last/@FactorInteger[n]==3, a=Length[First/@FactorInteger[n]]; If[a==3, b=First/@FactorInteger[n]; c=b[[1]]; d=b[[2]]; e=b[[3]]; If[ !PrimeQ[(c-1)/2]&&!PrimeQ[(d-1)/2]&&!PrimeQ[(e-1)/2], AppendTo[lst, n]]]], {n, 7!}]; lst CROSSREFS Cf. A001358, A005384, A005385, A006881, A007304, A111206, A157342, A157344, A157345, A157346, A157347, A157352, A157353, A157354 Sequence in context: A295699 A025387 A025378 * A224666 A161596 A275218 Adjacent sequences: A157352 A157353 A157354 * A157356 A157357 A157358 KEYWORD nonn AUTHOR Vladimir Joseph Stephan Orlovsky, Feb 27 2009 STATUS approved

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Last modified December 11 09:49 EST 2023. Contains 367722 sequences. (Running on oeis4.)