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Search: id:A067077
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| A067077 |
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Product of the prime factors of n equals the sum of the digits of n. |
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+0
1
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| 2, 3, 5, 6, 7, 24, 375, 392, 640, 2401, 4802, 4913, 6400, 7744, 17576, 42592, 64000
(list; graph; listen)
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OFFSET
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1,1
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EXAMPLE
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The prime factors of 375 are 3,5, which have product = 15, the sum of the digits of 375, so 375 is a term of the sequence.
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MATHEMATICA
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f[n_] := Module[{a, l, t, r}, a = FactorInteger[n]; l = Length[a]; t = Table[a[[i]][[1]], {i, 1, l}]; r = Product[t[[i]], {i, 1, l}]]; g[n_] := Module[{b, m, s}, b = IntegerDigits[n]; m = Length[b]; s = Sum[b[[i]], {i, 1, m}]]; Select[Range[2, 10^5], f[ # ] == g[ # ] &]
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CROSSREFS
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Cf. A006753.
Sequence in context: A090745 A002229 A077674 this_sequence A067183 A036587 A075145
Adjacent sequences: A067074 A067075 A067076 this_sequence A067078 A067079 A067080
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KEYWORD
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base,nonn
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AUTHOR
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Joseph L. Pe (joseph_l_pe(AT)hotmail.com), Feb 18 2002
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