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A131929
Number of prime factors of n that are contained in decimal representation of n.
5
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
OFFSET
1,132
COMMENTS
a(A050695(n)) = 0; a(A131930(n)) > 0;
a(A131931(n)) = n and a(m) <> n for m < A131931(n).
LINKS
EXAMPLE
a(230) = a(23*5*2) = #{2,23} = 2.
CROSSREFS
Sequence in context: A353499 A359372 A327861 * A100821 A139689 A204175
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Jul 30 2007
STATUS
approved