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A273291 A273289(n)^Omega(n), where Omega = A001222. 4

%I

%S 2,3,4,5,9,7,8,9,25,11,8,13,25,25,16,17,27,19,8,25,49,23,16,25,121,27,

%T 8,29,27,31,32,49,121,49,81,37,121,121,16,41,27,43,8,27,169,47,32,49,

%U 125,121,8,53,81,121,16,121,289,59,81,61,289,27,64,121,27,67,8,169,125

%N A273289(n)^Omega(n), where Omega = A001222.

%C a(n)>= A273290(n).

%C a(n) is by definition the power of a prime. It coincides with n iff n is also a power of prime (A246655).

%H Giuseppe Coppoletta, <a href="/A273291/b273291.txt">Table of n, a(n) for n = 2..10000</a>

%F a(n) = A273289(n)^A001222(n).

%e a(308) = 5^4 because Omega(308)=4 and the median of [2, 2, 7, 11] is (2+7)/2 = 4.5, whose next prime is 5. See A273290 for other examples.

%t Table[If[PrimeQ@ #, #, NextPrime@ #] &[Median@ #]^Length@ # &@ Flatten@ Apply[Table[#1, {#2}] &, FactorInteger@ n, 1], {n, 2, 70}] (* _Michael De Vlieger_, May 27 2016 *)

%o (Sage) def r(n): return [f[0] for f in factor(n) for _ in range(f[1])]

%o [next_prime(ceil(median(r(n)))-1)^sloane.A001222(n) for n in (2..70)]

%Y Cf. A273285, A273289, A273290, A079871, A001222, A246655.

%K nonn

%O 2,1

%A _Giuseppe Coppoletta_, May 25 2016

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Last modified August 21 05:48 EDT 2019. Contains 326162 sequences. (Running on oeis4.)