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A235154 Primes which have one or more occurrences of exactly two different digits. 20

%I

%S 13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97,101,113,

%T 131,151,181,191,199,211,223,227,229,233,277,311,313,331,337,353,373,

%U 383,433,443,449,499,557,577,599,661,677,727,733,757,773,787,797,811

%N Primes which have one or more occurrences of exactly two different digits.

%C The first term having a repeated digit is 101.

%H Colin Barker, <a href="/A235154/b235154.txt">Table of n, a(n) for n = 1..650</a>

%o (PARI) s=[]; forprime(n=10, 1000, if(#vecsort(eval(Vec(Str(n))),,8)==2, s=concat(s, n))); s

%o (PARI) is(n)=isprime(n) && #Set(digits(n))==2 \\ _Charles R Greathouse IV_, Feb 23 2017

%Y Cf. A235155-A235161, A030291.

%K nonn,base

%O 1,1

%A _Colin Barker_, Jan 04 2014

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Last modified July 14 16:21 EDT 2020. Contains 335729 sequences. (Running on oeis4.)