%I #9 Sep 19 2023 12:34:50
%S 151,157,1151,1153,1511,1523,1531,1543,1549,1553,1559,1567,1571,1579,
%T 1583,1597,2153,4153,4157,4159,5153,6151,7151,7159,9151,9157,10151,
%U 10159,11159,11503,11519,11527,11549,11551,11579,11587,11593,11597,12157,13151,13159
%N Prime numbers containing the string 15.
%H Vincenzo Librandi, <a href="/A243531/b243531.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) ~ n log n. - _Charles R Greathouse IV_, Jun 20 2014
%t Select[Prime[Range[2000]], !StringFreeQ[ToString[#], "15" ] &]
%t Select[Prime[Range[2000]],SequenceCount[IntegerDigits[#],{1,5}]>0&] (* _Harvey P. Dale_, Sep 19 2023 *)
%o (PARI) contains(n,k)=my(N=digits(n),K=digits(k)); for(i=0,#N-#K, for(j=1,#K,if(N[i+j]!=K[j],next(2))); return(1)); 0
%o is(n)=isprime(n) && contains(n,15) \\ _Charles R Greathouse IV_, Jun 20 2014
%Y Cf. similar sequences listed in A243529.
%K nonn,base,less
%O 1,1
%A _Vincenzo Librandi_, Jun 06 2014
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