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In prime factorization of n replace all primes with the greatest prime factor of n; a(1)=1.
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%I #13 Oct 25 2024 13:22:31

%S 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,

%T 169,27,343,29,125,31,32,121,289,49,81,37,361,169,625,41,343,43,1331,

%U 125,529,47,243,49,125,289,2197,53,81,121,2401,361,841,59,625,61

%N In prime factorization of n replace all primes with the greatest prime factor of n; a(1)=1.

%F a(n) = A006530(n)^A001222(n).

%F A068794(n) <= n <= a(n).

%F a(n) = A068794(n) iff n = 1 or n = p^k for some prime p, k > 0.

%e a(30) = a(2*3*5) = 5*5*5 = 125.

%p with(NumberTheory): A068795 := n -> max(PrimeFactors(n))^Omega(n):

%p seq(A068795(n), n = 1..61); # _Peter Luschny_, Oct 25 2024

%Y Cf. A001222, A006530, A068794.

%K nonn

%O 1,2

%A _Reinhard Zumkeller_, Mar 05 2002