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A088167 Number of earlier occurring divisors of n; a(1)=1. 2
1, 1, 2, 3, 2, 5, 2, 5, 3, 7, 2, 8, 2, 8, 6, 9, 2, 12, 2, 11, 5, 10, 2, 16, 5, 10, 5, 11, 2, 21, 2, 15, 6, 12, 8, 19, 2, 14, 4, 24, 2, 21, 2, 18, 11, 15, 2, 28, 3, 23, 5, 17, 2, 24, 11, 24, 6, 17, 2, 37, 2, 19, 9, 24, 8, 29, 2, 23, 7, 31, 2, 41, 2, 23, 13, 25, 8, 29, 2, 38, 7, 24, 2, 40 (list; graph; refs; listen; history; internal format)
OFFSET

1,3

COMMENTS

a(n) = #{k: 1<=k<n & n mod a(k) = 0};

a(n)=2 iff n is an odd prime;

a(A088168(n))=n and a(k)<>n for k < A088168(n).

CROSSREFS

Sequence in context: A073751 A108501 A166226 * A073893 A099552 A076199

Adjacent sequences:  A088164 A088165 A088166 * A088168 A088169 A088170

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Sep 21 2003

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Last modified February 17 19:13 EST 2012. Contains 206085 sequences.