Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A060681
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A060681 Largest difference between consecutive divisors of n (ordered by size). +0
8
1, 2, 2, 4, 3, 6, 4, 6, 5, 10, 6, 12, 7, 10, 8, 16, 9, 18, 10, 14, 11, 22, 12, 20, 13, 18, 14, 28, 15, 30, 16, 22, 17, 28, 18, 36, 19, 26, 20, 40, 21, 42, 22, 30, 23, 46, 24, 42, 25, 34, 26, 52, 27, 44, 28, 38, 29, 58, 30, 60, 31, 42, 32, 52, 33, 66, 34, 46, 35, 70, 36, 72, 37 (list; graph; listen)
OFFSET

2,2

COMMENT

Equivalently, a(n) = n - n/p, where p = A020639(n) is the smallest prime divisor of n.

REFERENCES

A. Balog, P. Erdos, and G. Tenenbaum, On Arithmetic Functions Involving Consecutive Divisors. In: Analytical Number Theory, pp. 77-90, Birkhauser, Basel, 1990.

EXAMPLE

For n=35, divisors={1,5,7,35}; differences={4,2,28}; a(35) = largest difference = 28 = 35 - 35/5.

MATHEMATICA

a[n_ ] := n-n/FactorInteger[n][[1, 1]]

CROSSREFS

Cf. A020639, A060680, A060682, A060683, A060685.

Sequence in context: A122376 A067240 A126080 this_sequence A060766 A029578 A054345

Adjacent sequences: A060678 A060679 A060680 this_sequence A060682 A060683 A060684

KEYWORD

nonn

AUTHOR

Labos E. (labos(AT)ana.sote.hu), Apr 19 2001

EXTENSIONS

Edited by Dean Hickerson (dean(AT)math.ucdavis.edu), Jan 22 2002

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified August 29 17:54 EDT 2008. Contains 143238 sequences.


AT&T Labs Research