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A065036
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Product of the cube of a prime (A030078) and a different prime.
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38
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24, 40, 54, 56, 88, 104, 135, 136, 152, 184, 189, 232, 248, 250, 296, 297, 328, 344, 351, 375, 376, 424, 459, 472, 488, 513, 536, 568, 584, 621, 632, 664, 686, 712, 776, 783, 808, 824, 837, 856, 872, 875, 904, 999, 1016, 1029, 1048, 1096, 1107, 1112
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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EXAMPLE
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a(4)= 56 since 56 = 2*2*2*7.
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MATHEMATICA
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Select[ Range[1500], Sort[ Transpose[ FactorInteger[ # ]] [[2]]] == {1, 3} & ]
Module[{upto=1200}, Select[(Union[Flatten[{#[[1]]^3 #[[2]], #[[1]]#[[2]]^3}&/@Subsets[Prime[Range[upto/8]], {2}]]]), #<=upto&]] (* Harvey P. Dale, May 23 2015 *)
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PROG
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(PARI) list(lim)=my(v=List(), t); forprime(p=2, (lim\2)^(1/3), t=p^3; forprime(q=2, lim\t, if(p==q, next); listput(v, t*q))); vecsort(Vec(v)) \\ Charles R Greathouse IV, Jul 20 2011
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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