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%I #7 Oct 15 2019 07:41:46
%S 4,15,35,39,51,95,115,87,155,111,123,215,235,159,371,183,302,335,219,
%T 511,395,415,267,623,291,303,482,327,339,791,554,1415,635,655,411,695,
%U 662,447,698,471,734,815,835,519,1211,543,842,1991,579,591,914,2167,2587
%N Smallest number k such that the sum of prime factors of k (counted with multiplicity) is n times a square > 1.
%C Smallest k such that sopfr(k) = n*q^2.
%C a(n) = A213386(n), except for n = 1, 105, 173, 213, 227, 287, …
%H Amiram Eldar, <a href="/A213420/b213420.txt">Table of n, a(n) for n = 1..10000</a>
%e a(105) = 3764 because 3764 = 2^2 * 941 and the sum of prime factors (counted with multiplicity) is 4 + 941 = 945 = 105*9 where 9 is a square.
%p with(numtheory):
%p sopfr:= proc(n) option remember;
%p add(i[1]*i[2], i=ifactors(n)[2])
%p end:
%p a:= proc(n) local k, p;
%p for k from 2 while irem(sopfr(k), n, 'p')>0 or
%p sqrt(p)<>floor(sqrt(p)) or p=1 do od; k
%p end:
%p seq (a(n), n=1..100);
%Y Cf. A213386, A212401.
%K nonn
%O 1,1
%A _Michel Lagneau_, Jun 11 2012
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