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A336445 Integers m such that m/sopf(m) is a prime number where sopf(m) is A008472(m), the sum of the distinct primes dividing m.

%I A336445 #15 Jul 24 2020 01:52:49
%S A336445 4,9,25,30,49,70,84,105,121,169,231,234,260,286,289,361,456,529,532,
%T A336445 627,646,805,841,897,961,1116,1364,1369,1581,1665,1681,1798,1849,1924,
%U A336445 2064,2150,2209,2632,2809,2967,3055,3339,3481,3526,3721,4489,4543,4824,5025,5041
%N A336445 Integers m such that m/sopf(m) is a prime number where sopf(m) is A008472(m), the sum of the distinct primes dividing m.
%C A336445 All squares of primes (A001248) are terms.
%H A336445 Michel Marcus, <a href="/A336445/b336445.txt">Table of n, a(n) for n = 1..1049</a> (terms up to 10^7)
%e A336445 4 is a term since sopf(4)=2 and 4/2 = 2 is a prime.
%e A336445 30 is a term since sopf(30)=10 and 30/10 = 3 is a prime.
%o A336445 (PARI) sopf(n)=vecsum(factor(n)[, 1]); \\ A008472
%o A336445 isokp(k) = my(q=k/sopf(k)); (denominator(q)==1) && isprime(q);
%Y A336445 Cf. A008472 (sopf).
%Y A336445 Subsequence of A071139.
%Y A336445 A001248 is a subsequence.
%Y A336445 Cf. A336296, A336297.
%K A336445 nonn
%O A336445 1,1
%A A336445 _Michel Marcus_, Jul 22 2020