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 A131929 Number of prime factors of n that are contained in decimal representation of n. 4
 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 0, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(A050695(n)) = 0; a(A131930(n)) > 0; a(A131931(n)) = n and a(m) <> n for m < A131931(n). LINKS R. Zumkeller, Table of n, a(n) for n = 1..10000 EXAMPLE a(230) = a(23*5*2) = #{2,23} = 2. CROSSREFS Cf. A131930, A131931. Sequence in context: A122257 A129950 A010051 * A100821 A139689 A073070 Adjacent sequences:  A131926 A131927 A131928 * A131930 A131931 A131932 KEYWORD nonn,base AUTHOR Reinhard Zumkeller, Jul 30 2007 STATUS approved

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