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%I #10 Apr 03 2023 10:36:13
%S 2,5,773,3373,3947,4643,5113,6397,6967,7937,15647,16823,24373,33547,
%T 34337,37643,56983,57853,59743,62383,63347,63617,69337,72467,72617,
%U 75653,76367,87643,92683,97883,98317,121997,124337,163853,213613,236653,242467,242797
%N Left-truncatable primes p with property that prepending any single decimal digit to p does not produce a prime.
%H Chris Caldwell, The Prime Glossary, <a href="https://t5k.org/glossary/xpage/LeftTruncatablePrime.html">Left-truncatable prime</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/TruncatablePrime.html">Truncatable Prime</a>
%H <a href="/index/Tri#tprime">Index entries for sequences related to truncatable primes</a>
%F A024785 INTERSECT A155762.
%e 3373 belongs to this sequence because 3373, 373, 73 and 3 are all prime; k*10^4 + 3373, for k = 1 to 9, are all composite.
%o (PARI) for(n=2, 242797, v=n; while(isprime(n), c=n; n=lift(Mod(c, 10^(#Str(c)-1))); if(!(#Str(c)-#Str(n)==1), break)); if(n==0, s=#Str(v); t=0; for(k=1, 9, if(isprime(k*10^s+v), break, t++)); if(t==9, print1(v, ", "))); n=v);
%Y Subsequence of A024785 and of A155762.
%K nonn,base,fini
%O 1,1
%A _Arkadiusz Wesolowski_, Apr 12 2014
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