Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A071364
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A071364 Smallest number with same sequence of exponents in canonical prime factorization as n. +0
12
1, 2, 2, 4, 2, 6, 2, 8, 4, 6, 2, 12, 2, 6, 6, 16, 2, 18, 2, 12, 6, 6, 2, 24, 4, 6, 8, 12, 2, 30, 2, 32, 6, 6, 6, 36, 2, 6, 6, 24, 2, 30, 2, 12, 12, 6, 2, 48, 4, 18, 6, 12, 2, 54, 6, 24, 6, 6, 2, 60, 2, 6, 12, 64, 6, 30, 2, 12, 6, 30, 2, 72, 2, 6, 18, 12, 6, 30, 2, 48, 16, 6, 2, 60, 6, 6, 6, 24 (list; graph; listen)
OFFSET

1,2

COMMENT

A046523(a(n))=A046523(n); A046523(n)<=a(n)<=n; A001221(a(n))=A001221(n), A001222(a(n))=A001222(n); A020639(a(n))=2, A006530(a(n))=A000040(A001221(n))<=A006530(n); A000005(a(n))=A000005(n);

a(a(n))=a(n); a(n)=2^k iff n=p^k, p prime, k>0 (A000961); if n>1 is not a prime power, then a(n) mod 6 = 0; range of values = A055932, as distinct prime factors of a(n) are consecutive: a(n)=n iff n=A055932(k) for some k;

a(A003586(n))=A003586(n).

LINKS

Daniel Forgues, Table of n, a(n) for n=1..100000

FORMULA

In prime factorization of n, replace least prime by 2, next least by 3, etc.

EXAMPLE

a(105875) = a(5*5*5*7*11*11) = 2*2*2*3*5*5 = 600.

MATHEMATICA

Table[ e = Last /@ FactorInteger[n]; Product[Prime[i]^e[[i]], {i, Length[e]}], {n, 88}] (*Chandler*)

CROSSREFS

Cf. A071365, A071366.

Sequence in context: A119655 A083260 A046523 this_sequence A067824 A107067 A046801

Adjacent sequences: A071361 A071362 A071363 this_sequence A071365 A071366 A071367

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), May 21 2002

EXTENSIONS

Extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), Sep 23 2005

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 24 19:42 EST 2009. Contains 167435 sequences.


AT&T Labs Research