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 A268588 Numbers n such that n, n + 1, n + 2, n + 3 and n + 4 are products of exactly three primes. 1
 602, 2522, 2523, 4202, 4921, 4922, 5034, 5282, 7730, 18241, 18242, 18571, 19129, 21931, 23161, 23305, 25203, 25553, 25554, 27290, 27291, 29233, 30354, 30793, 32035, 33843, 34561, 35714, 36001, 36835, 40313, 40314, 40394, 45265, 55361, 67609, 69667, 70202, 72721 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Subsequence of A045941. - Zak Seidov, Jan 29 2017 LINKS Chai Wah Wu, Table of n, a(n) for n = 1..11023 EXAMPLE a(1) = 602: 602 = 2 * 7 * 43; 603 = 3 * 3 * 67; 604 = 2 * 2 * 151; 605 = 5 * 11 * 11; 606 = 2 * 3 * 101 are all products of three primes. a(4) = 4202 : 4202 = 2 * 11 * 191; 4203 = 3 * 3 * 467; 4204 = 2 * 2 * 1051; 4205 = 5 * 29 * 29; 4206 = 2 * 3 * 701 are all products of three primes. MAPLE with(numtheory): A268588:= proc() if bigomega(n)=3 and bigomega(n+1)=3 and bigomega(n+2)=3 and bigomega(n+3)=3 and bigomega(n+4)=3 then RETURN (n); fi; end: seq(A268588(), n=1..100000); MATHEMATICA Select[Range[100000], PrimeOmega[#] == 3 && PrimeOmega[# + 1] == 3 && PrimeOmega[# + 2] == 3 && PrimeOmega[# + 3] == 3 && PrimeOmega[# + 4] == 3 &] SequencePosition[PrimeOmega[Range[73000]], {3, 3, 3, 3, 3}][[All, 1]] (* Harvey P. Dale, Sep 03 2021 *) PROG (PARI) for(n = 1, 50000, bigomega(n)==3 & bigomega(n+1)==3 & bigomega(n+2)==3 & bigomega(n+3)==3 & bigomega(n+4)==3 & print1(n, ", ")) (Magma) IsP3:=func< n | &+[k[2]: k in Factorization(n)] eq 3 >; [ n: n in [2..50000] | IsP3(n) and IsP3(n+1) and IsP3(n+2) and IsP3(n+3) and IsP3(n+4)]; CROSSREFS Cf. A056809, A113789, A124057, A045941. Sequence in context: A124057 A252435 A045941 * A251462 A356893 A281561 Adjacent sequences: A268585 A268586 A268587 * A268589 A268590 A268591 KEYWORD nonn AUTHOR K. D. Bajpai, Feb 07 2016 EXTENSIONS Comment removed by Zak Seidov, Jan 29 2017 STATUS approved

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Last modified October 3 10:37 EDT 2023. Contains 365861 sequences. (Running on oeis4.)