A273799 Numbers n such that the decimal digits of n-phi(n) are a permutation of those of n.

91, 342, 351, 627, 684, 874, 950, 1824, 2114, 2318, 2715, 3051, 3171, 3172, 3402, 3411, 4228, 6344, 6804, 7346, 8414, 8456, 8474, 9093, 9125, 9191, 9254, 9500, 9531, 9548, 9672, 9824, 9950, 15804, 18010, 18312, 18508, 18930, 19190, 21028, 22126, 23218, 24180, 24716

Offset: 1

Author

Paolo P. Lava, May 31 2016

Keywords

• nonn
• easy
• base

Examples

			91 - phi(91) = 91 - 72 = 19;
342 - phi(342) = 342 - 108 = 234.
		

Links

• Paolo P. Lava, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A051953, A115921.

Programs

Maple

with(numtheory): P:=proc(q) local a,b,c,d,k,n; for n from 1 to q do a:=n; b:=n-phi(n);
if ilog10(a)=ilog10(b) then c:=[]; d:=[]; for k from 1 to ilog10(n)+1 do
c:=[op(c),(a mod 10)]; a:=trunc(a/10); d:=[op(d),(b mod 10)]; b:=trunc(b/10); od;
c:=sort(c); d:=sort(d); if c=d then print(n); fi; fi; od; end: P(10^25);

Mathematica

Select[Range[25000], Sort@ IntegerDigits@ # == Sort@ IntegerDigits[# - EulerPhi@ #] &] (* Michael De Vlieger, Jun 01 2016 *)