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%I #13 Jun 18 2022 19:29:11
%S 1,1021,1201,2011,7687,7867,8677,10211,10271,10321,12011,12041,12071,
%T 12101,12301,12343,12401,12433,12601,14323,16787,17021,20011,20101,
%U 20161,20411,20611,21001,21011,21031,21061,21101,21401,21433,21601,21701,22343,22433
%N Numbers k such that k, sigma(k) and phi(k) have the same decimal digits.
%H Donovan Johnson, <a href="/A082059/b082059.txt">Table of n, a(n) for n = 1..1000</a>
%e n = 89767, sigma(n) = 89768, phi(n) = 89766.
%t Select[Range[25000],Union[IntegerDigits[#]] == Union[ IntegerDigits[ DivisorSigma[ 1,#]]] == Union[IntegerDigits[EulerPhi[#]]]&] (* _Harvey P. Dale_, Jun 12 2014 *)
%o (PARI) c=0; for(n=1, 324773, m=n; nd=vector(10); for(j=1, 6, r=m%10; nd[r+1]=1; m=m\10; if(m==0, j=6)); s=sigma(n); m=s; sd=vector(10); for(j=1, 6, r=m%10; sd[r+1]=1; m=m\10; if(m==0, j=6)); for(j=1, 10, if(nd[j]<>sd[j], next(2))); p=eulerphi(n); m=p; pd=vector(10); for(j=1, 6, r=m%10; pd[r+1]=1; m=m\10; if(m==0, j=6)); for(j=1, 10, if(nd[j]<>pd[j], next(2))); c++; write("b082059.txt", c " " n)) \\ _Donovan Johnson_, Feb 28 2013
%Y Cf. A000203 (sigma), A000010 (phi).
%K nonn,base
%O 1,2
%A _Labos Elemer_, Apr 04 2003
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