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A157354 Products of 3 distinct safe primes. 3
385, 805, 1265, 1645, 1771, 2065, 2585, 2905, 3245, 3619, 3745, 4543, 4565, 5405, 5845, 5885, 6265, 6391, 6785, 7567, 7945, 8239, 9185, 9205, 9499, 9545, 9845, 11891, 12145, 12305, 12485, 12565, 12859, 13363, 13405, 13783, 13865, 14465, 14927 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

385=5*7*11; 5,7 and 11 are safe prime numbers,...

LINKS

Table of n, a(n) for n=1..39.

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

Sequence in context: A013591 A152941 A229853 * A065110 A200525 A225711

Adjacent sequences:  A157351 A157352 A157353 * A157355 A157356 A157357

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Feb 27 2009

STATUS

approved

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Last modified August 20 11:39 EDT 2017. Contains 290835 sequences.