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A071364 Smallest number with same sequence of exponents in canonical prime factorization as n. 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; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

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 * A067824 A107067 A046801

Adjacent sequences:  A071361 A071362 A071363 * 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

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Last modified February 17 04:58 EST 2012. Contains 205985 sequences.