id:A088167 - OEIS Search Results

Search: id:A088167

Displaying 1-1 of 1 results found.

page 1

Number of earlier occurring divisors of n; a(1)=1.

+0
3

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; listen)

	OFFSET	`1,3`
	COMMENT	`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 this_sequence A073893 A099552 A076199` `Adjacent sequences: A088164 A088165 A088166 this_sequence A088168 A088169 A088170`
	KEYWORD	`nonn`
	AUTHOR	`Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Sep 21 2003`

page 1

Search completed in 0.002 seconds

Last modified December 18 21:37 EST 2009. Contains 171024 sequences.

AT&T Labs Research