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Some permutation of digits is a prime.
4

%I #24 Jul 14 2015 16:13:55

%S 2,3,5,7,11,13,14,16,17,19,20,23,29,30,31,32,34,35,37,38,41,43,47,50,

%T 53,59,61,67,70,71,73,74,76,79,83,89,91,92,95,97,98,101,103,104,106,

%U 107,109,110,112,113,115,118,119,121,124,125,127,128,130,131,133

%N Some permutation of digits is a prime.

%C Conjecture: a(n) ~ 3n/2. - _Charles R Greathouse IV_, Sep 19 2012

%D M. Le, On Smarandache Pseudo-Primes of Second Kind, Smarandache Notions Journal, Vol. 10, No. 1-2-3, 1999, 180.

%H Eric M. Schmidt, <a href="/A007933/b007933.txt">Table of n, a(n) for n = 1..10000</a>

%H F. Smarandache, <a href="http://www.gallup.unm.edu/~smarandache/OPNS.pdf">Only Problems, Not Solutions!</a>.

%t t ={};Do[list1 = Permutations[IntegerDigits[n]];If[Length[Select[Table[FromDigits[n],{n,list1}], PrimeQ]] > 0,AppendTo[t, n]], {n, 133}]; t (* _Jayanta Basu_, Apr 24 2013 *)

%t Select[Range@ 133, AnyTrue[FromDigits /@ Permutations@ IntegerDigits@ #, PrimeQ] &] (* _Michael De Vlieger_, Jul 14 2015, Version 10 *)

%o (PARI) is(n)=if(n%3==0, return(n/10^valuation(n,10)==3)); my(d=digits(n),t=#d); for(i=0,t!-1, if(isprime(fromdigits(vecextract(d,numtoperm(t,i)))), return(1))); 0 \\ _Charles R Greathouse IV_, Jul 14 2015

%K nonn,base

%O 1,1

%A R. Muller