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A114065 Numbers k such that the digits of phi(k) and sigma(k) are permutations of those of k.

%I A114065 #20 Jul 22 2021 07:53:12
%S A114065 1,3014685,21638943,170726121,207380169,215341083,233559801,234511083,
%T A114065 321634251,1620475083,1982243007,2019804093,2084013063,2185499607,
%U A114065 2410658685,2653713819,2741018409,2859457041,3018792645,3075268041,3148920504,3701484126,4071408255
%N A114065 Numbers k such that the digits of phi(k) and sigma(k) are permutations of those of k.
%C A114065 Intersection of A115920 and A115921.
%H A114065 Giovanni Resta, <a href="/A114065/b114065.txt">Table of n, a(n) for n = 1..520</a> (terms < 10^12)
%e A114065 sigma(3014685) = 5431680 and phi(3014685) = 1586304.
%o A114065 (Python)
%o A114065 from sympy import totient, divisor_sigma
%o A114065 A114065_list = [n for n in range(1,10**7) if sorted(str(divisor_sigma(n))) == sorted(str(totient(n))) == sorted(str(n))] # _Chai Wah Wu_, Dec 13 2015
%o A114065 (PARI) isok(n) = (d = vecsort(digits(n))) && (ds = vecsort(digits(sigma(n)))) && (d == ds) && (de = vecsort(digits(eulerphi(n)))) && (ds == de); \\ _Michel Marcus_, Dec 13 2015
%Y A114065 Cf. A115920, A115921, A175795.
%Y A114065 Cf. A000010, A000203.
%K A114065 nonn,base
%O A114065 1,2
%A A114065 _Giovanni Resta_, Feb 13 2006