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A068795
In prime factorization of n replace all primes with the greatest prime factor of n; a(1)=1.
9
1, 2, 3, 4, 5, 9, 7, 8, 9, 25, 11, 27, 13, 49, 25, 16, 17, 27, 19, 125, 49, 121, 23, 81, 25, 169, 27, 343, 29, 125, 31, 32, 121, 289, 49, 81, 37, 361, 169, 625, 41, 343, 43, 1331, 125, 529, 47, 243, 49, 125, 289, 2197, 53, 81, 121, 2401, 361, 841, 59, 625, 61
OFFSET
1,2
FORMULA
a(n) = A006530(n)^A001222(n).
A068794(n) <= n <= a(n).
a(n) = A068794(n) iff n = 1 or n = p^k for some prime p, k > 0.
EXAMPLE
a(30) = a(2*3*5) = 5*5*5 = 125.
MAPLE
with(NumberTheory): A068795 := n -> max(PrimeFactors(n))^Omega(n):
seq(A068795(n), n = 1..61); # Peter Luschny, Oct 25 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Mar 05 2002
STATUS
approved