Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A090624
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A090624 If n=product(pj^ej), i.e. written in its prime factorization, then a(n)=max_j{(pj-1)*ej}. +0
4
1, 2, 2, 4, 2, 6, 3, 4, 4, 10, 2, 12, 6, 4, 4, 16, 4, 18, 4, 6, 10, 22, 3, 8, 12, 6, 6, 28, 4, 30, 5, 10, 16, 6, 4, 36, 18, 12, 4, 40, 6, 42, 10, 4, 22, 46, 4, 12, 8, 16, 12, 52, 6, 10, 6, 18, 28, 58, 4, 60, 30, 6, 6, 12, 10, 66, 16, 22, 6, 70, 4, 72, 36, 8, 18, 10, 12, 78, 4, 8, 40, 82, 6 (list; graph; listen)
OFFSET

2,2

COMMENT

The highest power of k dividing n! (A090622) is close to, but below, n/a(k).

FORMULA

a(p)=p-1. a(p^m)=(p-1)*m. a(b*c)=max(a(b), a(c)) for b and c coprime.

EXAMPLE

72=2^3*3^2 so a(72)=max((2-1)*3,(3-1)*2)=max(3,4)=4.

CROSSREFS

Sequence in context: A137502 A143112 A167272 this_sequence A099735 A091279 A096002

Adjacent sequences: A090621 A090622 A090623 this_sequence A090625 A090626 A090627

KEYWORD

nonn

AUTHOR

Henry Bottomley (se16(AT)btinternet.com), Dec 06 2003

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 November 23 17:09 EST 2009. Contains 167438 sequences.


AT&T Labs Research