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A179693
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Products of 4 distinct primes (p^4*q*r*s).
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10
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1680, 2640, 3120, 3696, 4080, 4368, 4560, 5520, 5670, 5712, 6160, 6384, 6864, 6960, 7280, 7440, 7728, 8880, 8910, 8976, 9520, 9744, 9840, 10032, 10320, 10416, 10530, 10608, 10640, 11280, 11440, 11856, 12144, 12432, 12474, 12720, 12880, 13770
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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
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MATHEMATICA
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f[n_]:=Sort[Last/@FactorInteger[n]]=={1, 1, 1, 4}; Select[Range[15000], f]
Take[Union[First[#]^4 Times@@Rest[#]&/@Flatten[ Permutations/@ Subsets[ Prime[Range[20]], {4}], 1]], 50] (* Harvey P. Dale, Jan 26 2013 *)
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CROSSREFS
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Cf. A006881, A007304, A065036, A085986, A085987, A092759, A178739, A179642, A179643, A179644, A179645, A179646, A179664, A179665, A179666, A179667, A179668, A179669, A179670, A179671, A179672, A179688, A179689, A179690, A179691, A179692.
Sequence in context: A156425 A093787 A175749 * A175340 A181928 A060095
Adjacent sequences: A179690 A179691 A179692 * A179694 A179695 A179696
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KEYWORD
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nonn
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AUTHOR
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Vladimir Joseph Stephan Orlovsky, Jul 24 2010
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STATUS
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approved
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