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A224906 Prime numbers p such that 10^(j-1) < p < 10^j and p + 10^(j+k) are also prime numbers for k = 0 to 4.

%I A224906 #17 Jan 30 2020 06:42:22
%S A224906 37957,1115239,2757649,2884279,3125779,3169459,3384583,3405037,
%T A224906 4237603,4746139,4769239,4861261,5074831,5080081,5194951,5295877,
%U A224906 5681899,5980981,6110593,6330043,7025101,7214773,7233883,8010589,8068969,8323153,8462131,8653651,9460723
%N A224906 Prime numbers p such that 10^(j-1) < p < 10^j and p + 10^(j+k) are also prime numbers for k = 0 to 4.
%C A224906 Only 656 primes have this property in the first 60000000 primes.
%H A224906 Pierre CAMI, <a href="/A224906/b224906.txt">Table of n, a(n) for n = 1..656</a>
%e A224906 37957, 137957, 1037957, 10037957, 100037957, 1000037957 are all prime numbers. Hence, a(1) = 37957 as it is the smallest prime with this property.
%o A224906 (PFGW & SCRIPTIFY) the file prem.txt with the 60000000 first primes
%o A224906 SCRIPT
%o A224906 DIM mm,1
%o A224906 DIM n
%o A224906 DIM ss,0
%o A224906 DIM cc
%o A224906 DIM pp
%o A224906 DIM qq
%o A224906 DIMS t
%o A224906 OPENFILEIN myf,prem.txt
%o A224906 OPENFILEOUT myfile,a(1).txt
%o A224906 LABEL a
%o A224906 GETNEXT qq,myf
%o A224906 IF qq>10^mm THEN SET mm,mm+1
%o A224906 SET ss,ss+1
%o A224906 SET cc,1
%o A224906 SET n,0
%o A224906 LABEL b
%o A224906 SET n,n+1
%o A224906 SET pp,qq+10^(n+mm)
%o A224906 SETS t,%d,%d\,;pp;cc
%o A224906 PRP pp,t
%o A224906 IF ISPRP THEN SET cc,cc+1
%o A224906 IF ISPRP THEN GOTO b
%o A224906 IF ss>59999999 THEN END
%o A224906 IF cc<6 THEN GOTO a
%o A224906 SETS t,%d,%d\,;qq;cc
%o A224906 WRITE myfile,t
%o A224906 GOTO a
%Y A224906 Cf. A124001.
%K A224906 nonn
%O A224906 1,1
%A A224906 _Pierre CAMI_, Jul 25 2013