%I #12 Oct 16 2019 23:50:14
%S 11,113,199,211,223,227,229,233,277,311,331,337,433,443,449,499,557,
%T 577,599,661,677,733,773,811,877,881,883,887,911,977,991,997,1009,
%U 1033,1103,1109,1117,1123,1129,1151,1153,1163,1171,1181,1187,1193,1223,1229
%N Primes containing at least one pair of consecutive equal digits.
%H Charles R Greathouse IV, <a href="/A050758/b050758.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) ~ n log n. - _Charles R Greathouse IV_, Aug 29 2015
%t Select[Prime[Range[205]],MemberQ[Differences[IntegerDigits[#]],0]&] (* _Jayanta Basu_, May 31 2013 *)
%t Select[Prime[Range[300]],SequenceCount[IntegerDigits[#],{x_,x_}]>0&] (* The program uses the SequenceCount function from Mathematica version 10 *) (* _Harvey P. Dale_, Feb 20 2016 *)
%o (PARI) is(n)=my(d=digits(n)); for(i=2,#d,if(d[i]==d[i-1], return(isprime(n)))); 0 \\ _Charles R Greathouse IV_, Aug 29 2015
%Y Cf. A043096, A000040, A050757, A029743.
%K nonn,base
%O 1,1
%A _Patrick De Geest_, Sep 15 1999
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