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%I A114064 #8 Jul 22 2021 01:58:55
%S A114064 2,4,12,16,25,36,48,64,75,80,81,100,112,121,144,162,192,208,225,240,
%T A114064 256,272,289,300,320,324,336,363,368,400,405,448,484,512,529,560,567,
%U A114064 576,592,624,688,700,704,720,729,752,768,784,810,816,841,848,867,900
%N A114064 Numbers k such that tau(k) does not divide sigma(k)*phi(k), where tau(k) = A000005(k).
%e A114064 tau(400) = 15 = 3*5 does not divide phi(400)*sigma(400) = 153760 = 2^5 * 5 * 31^2.
%o A114064 (PARI) isok(n) = sigma(n)*eulerphi(n) % numdiv(n); \\ _Michel Marcus_, Jan 08 2014
%K A114064 nonn
%O A114064 1,1
%A A114064 _Giovanni Resta_, Feb 13 2006

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