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%I #22 Jun 22 2019 09:17:08
%S 39,55,354,578,1634,1644,6604,8253,9825,12573,13516,14749,15244,16684,
%T 18669,18672,19276,19564,21032,22225,25305,28449,29853,31688,33633,
%U 35793,41261,41768,41949,42813,48013,50670,54048,59750,60804,63609,63869,65265,78832
%N Numbers k such that sopfr(k) = tau(k)^2.
%C For numbers k that satisfy the condition, tau(k) will always be even because tau(k) is odd only if k is a square, but if k is a square then sopfr(k) is even (because every prime appears with an even exponent) and thus it cannot be equal to tau(k)^2 which is odd as tau(k). - _Giovanni Resta_, May 24 2018
%H Amiram Eldar, <a href="/A305026/b305026.txt">Table of n, a(n) for n = 1..1000</a>
%F k such that A001414(k) = A000005(k)^2.
%t Rest@ Select[Range[10^5], Total[Times @@@ FactorInteger@ #] == DivisorSigma[0, #]^2 &] (* _Michael De Vlieger_, May 27 2018 *)
%o (PARI) isok(n) = my(f=factor(n)); sum(k=1,#f~,f[k,1]*f[k,2]) == numdiv(n)^2; \\ _Michel Marcus_, May 24 2018
%Y Cf. A000005, A001414, A078511.
%K nonn
%O 1,1
%A _Parker Grootenhuis_, May 23 2018
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