A243356 - OEIS

A243356

Numbers n such that n and phi(n) have no common digits.

2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 15, 16, 18, 20, 22, 24, 27, 30, 32, 33, 34, 35, 36, 39, 40, 44, 46, 48, 51, 54, 55, 56, 57, 62, 64, 65, 66, 68, 69, 70, 74, 75, 77, 78, 80, 81, 82, 85, 86, 87, 88, 90, 91, 92, 93, 95, 96, 98, 99, 105, 106, 108, 111, 112

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OFFSET

1,1

LINKS

Colin Barker, Table of n, a(n) for n = 1..3000

EXAMPLE

108 is in the sequence because phi(108) = 36, which has no digits in common with 108.

MATHEMATICA

Select[Range[200], Intersection[IntegerDigits[#], IntegerDigits[EulerPhi[#]]]=={}&] (* Harvey P. Dale, Feb 19 2024 *)

PROG

(PARI) s=[]; for(n=1, 300, if(setintersect(vecsort(digits(n), , 8), vecsort(digits(eulerphi(n)), , 8))==[], s=concat(s, n))); s

CROSSREFS