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A015708 Numbers n such that n | (phi(n) * sigma(n)) but (phi(n) + sigma(n))/n does not increase. 0

%I

%S 1,84,120,162,234,252,270,486,540,588,648,672,819,936,1350,1458,1536,

%T 1550,1638,1764,1782,1800,1872,1920,2268,2325,3000,3042,3240,3276,

%U 3402,3564,3724,3780,4116,4374,4464,4650,4680,4704,5292,5376

%N Numbers n such that n | (phi(n) * sigma(n)) but (phi(n) + sigma(n))/n does not increase.

%H Richard K. Guy, <a href="https://www.jstor.org/stable/2974586">Divisors and desires</a>, Amer. Math. Monthly, 104 (1997), 359-360.

%K nonn

%O 1,2

%A _Robert G. Wilson v_

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Last modified August 12 05:33 EDT 2020. Contains 336438 sequences. (Running on oeis4.)