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A082059 Numbers n such that n, sigma(n) and phi(n) have the same decimal digits. 2
1, 1021, 1201, 2011, 7687, 7867, 8677, 10211, 10271, 10321, 12011, 12041, 12071, 12101, 12301, 12343, 12401, 12433, 12601, 14323, 16787, 17021, 20011, 20101, 20161, 20411, 20611, 21001, 21011, 21031, 21061, 21101, 21401, 21433, 21601, 21701, 22343, 22433 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Donovan Johnson, Table of n, a(n) for n = 1..1000

EXAMPLE

n = 89767, sigma(n) = 89768, phi(n) = 89766.

MATHEMATICA

Select[Range[25000], Union[IntegerDigits[#]] == Union[ IntegerDigits[ DivisorSigma[ 1, #]]] == Union[IntegerDigits[EulerPhi[#]]]&] (* Harvey P. Dale, Jun 12 2014 *)

PROG

(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

CROSSREFS

Cf. A000005, A000010.

Sequence in context: A209620 A179032 A179033 * A081633 A020388 A306596

Adjacent sequences:  A082056 A082057 A082058 * A082060 A082061 A082062

KEYWORD

nonn,base

AUTHOR

Labos Elemer, Apr 04 2003

STATUS

approved

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Last modified December 4 04:49 EST 2021. Contains 349469 sequences. (Running on oeis4.)