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A079866
a(1)=1 and for n>1: floor(n^(1/Omega(n))), where Omega(n) is the total number of prime factors of n (A001222).
7
1, 2, 3, 2, 5, 2, 7, 2, 3, 3, 11, 2, 13, 3, 3, 2, 17, 2, 19, 2, 4, 4, 23, 2, 5, 5, 3, 3, 29, 3, 31, 2, 5, 5, 5, 2, 37, 6, 6, 2, 41, 3, 43, 3, 3, 6, 47, 2, 7, 3, 7, 3, 53, 2, 7, 2, 7, 7, 59, 2, 61, 7, 3, 2, 8, 4, 67, 4, 8, 4, 71, 2, 73, 8, 4, 4, 8, 4, 79, 2, 3, 9, 83, 3, 9, 9, 9, 3, 89, 3, 9, 4, 9, 9, 9, 2
OFFSET
1,2
COMMENTS
a(n) <= A079868(n).
A020639(n) <= a(n) <= A006530(n);
a(m) = A079868(m) = A079870(m) iff m is a prime power (A000961).
LINKS
MAPLE
A079866 := proc(n)
root[numtheory[bigomega](n)](n) ;
floor(%) ;
end proc:
seq(A079866(n), n=1..97) ; # R. J. Mathar, Sep 07 2016
MATHEMATICA
Join[{1}, Table[Floor[n^(1/PrimeOmega[n])], {n, 2, 20}]] (* G. C. Greubel, Sep 16 2016 *)
PROG
(PARI) a(n) = if (n==1, 1, sqrtnint(n, bigomega(n))); \\ Michel Marcus, Sep 09 2016
CROSSREFS
A079867(n) = a(n)^A001222(n).
Sequence in context: A067695 A285336 A273282 * A134332 A276632 A273288
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Jan 13 2003
STATUS
approved