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A189984
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Numbers with prime factorization pqrst^3.
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3
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9240, 10920, 14280, 15960, 17160, 19320, 20790, 22440, 24024, 24360, 24570, 25080, 26040, 26520, 29640, 30360, 31080, 31416, 32130, 34440, 35112, 35880, 35910, 36120, 37128, 38280, 38610, 38760, 39480, 40040, 40920, 41496, 42504, 43470
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OFFSET
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1,1
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LINKS
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T. D. Noe, Table of n, a(n) for n = 1..1000
Will Nicholes, Prime Signatures
Index to sequences related to prime signature
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MATHEMATICA
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f[n_]:=Sort[Last/@FactorInteger[n]]=={1, 1, 1, 1, 3}; Select[Range[80000], f]
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PROG
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(PARI) list(lim)=my(v=List(), t1, t2, t3, t4); forprime(p=2, sqrtnint(lim\210, 3), t1=p^3; forprime(q=2, lim\(30*t1), if(q==p, next); t2=q*t1; forprime(r=2, lim\(6*t2), if(r==p || r==q, next); t3=r*t2; forprime(s=2, lim\(2*t3), if(s==p || s==q || s==r, next); t4=s*t3; forprime(t=2, lim\t4, if(t==p || t==q || t==r || t==s, next); listput(v, t4*t)))))); Set(v) \\ Charles R Greathouse IV, Aug 25 2016
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CROSSREFS
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Cf. A179667, A179693.
Sequence in context: A031594 A262508 A272596 * A092005 A236512 A031848
Adjacent sequences: A189981 A189982 A189983 * A189985 A189986 A189987
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KEYWORD
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nonn
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AUTHOR
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Vladimir Joseph Stephan Orlovsky, May 03 2011
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STATUS
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approved
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