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%I #35 Oct 12 2020 18:49:45
%S 1,2,4,6,8,9,12,16,18,24,32,36,40,48,54,56,60,64,72,80,84,88,96,104,
%T 108,128,132,136,144,152,156,162,180,184,192,204,216,225,228,232,240,
%U 248,252,256,276,288,296,324,328,344,348,360,372,376,384,396,424,432,441,444,448,450
%N Numbers n where phi(n)|n or tau(n)|n.
%C Phi(n) is Euler totient function (A000010); tau(n) is the number of divisors of n (A000005).
%C Union of A007694 and A033950. - _Michel Marcus_, Jul 15 2014
%H Harvey P. Dale, <a href="/A245047/b245047.txt">Table of n, a(n) for n = 1..1000</a>
%p select(t -> (t mod numtheory:-phi(t) = 0) or (t mod numtheory:-tau(t) = 0), [$1..1000]); # _Robert Israel_, Jul 15 2014
%t Select[Range[500],AnyTrue[{#/EulerPhi[#],#/DivisorSigma[0,#]},IntegerQ]&] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Oct 12 2020 *)
%o (PARI) isok(n) = !((n % eulerphi(n)) && (n % numdiv(n))); \\ _Michel Marcus_, Jul 15 2014
%Y Cf. A000005, A000010, A007694, A033950, A235353.
%K nonn
%O 1,2
%A _Reinhard Muehlfeld_, Jul 13 2014
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