A249373 - OEIS

%I #24 Dec 21 2016 16:30:12

%S 3,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97,

%T 107,109,113,127,131,137,139,149,151,163,167,173,179,191,193,197,211,

%U 223,229,233,239,241,257,263,269,277,281,283,293,313

%N Prime numbers Q such that the concatenation Q,d,Q is prime for at least one d in the set {1, 2, 3, 4, 5, 6, 7, 8, 9}.

%H Pierre CAMI, <a href="/A249373/b249373.txt">Table of n, a(n) for n = 1..10000</a>

%e 313, 353, 373 as 383 are prime numbers so a(1)=3.

%e 727, 757, 787 as 797 are prime numbers so a(2)=7.

%t Select[Prime[Range[100]],AnyTrue[FromDigits/@Table[Join[ IntegerDigits[ #], {n},IntegerDigits[#]],{n,9}],PrimeQ]&] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Dec 21 2016 *)

%o (PFGW & SCRIPT), pre10.txt file with the first 10000000 prime numbers.

%o SCRIPT

%o DIM i,0

%o DIM j

%o DIM k

%o DIM n,1

%o DIM o

%o OPENFILEOUT myf,a(n).txt

%o OPENFILEIN maf,pre10.txt

%o GETNEXT j,maf

%o LABEL loop1

%o GETNEXT j,maf

%o IF j>10^n THEN SET n,n+1

%o SET o,0

%o LABEL loop2

%o SET o,o+1

%o IF o>9 THEN  GOTO loop1

%o SET k,j*10^(n+1)+o*10^n+j

%o PRP k

%o IF ISPRP THEN GOTO w

%o GOTO loop2

%o LABEL w

%o SET i,i+1

%o WRITE myf,j

%o IF i>9999 THEN END

%o GOTO loop1

%o (PARI) lista(nn) = {forprime(p=2, nn, len = #Str(p); if (sum(i=1, 9, isprime(p+(10*p+i)*10^len)), print1(p, ", ")););} \\ _Michel Marcus_, Oct 28 2014

%Y Cf. A249350, A249374, A249375, A249376, A249377, A249378, A249379, A249380, A249381.

%K nonn,base

%O 1,1

%A _Pierre CAMI_, Oct 27 2014