This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A264814 #17 Sep 08 2022 08:46:14 %S A264814 7,9,11,13,33,37,39,41,47,57,59,61,69,71,77,79,81,83,101,103,129,149, %T A264814 181,187,189,191,193,207,217,229,231,241,289,291,299,301,303,307,317, %U A264814 333,347,359,373,377,383,387,409,439,451,467,473,487,489,509,517,527 %N A264814 Numbers k such that concatenate(k,k+1,k) is prime. %C A264814 Motivated by sequence A068660 which lists these primes. %H A264814 Michael S. Branicky, <a href="/A264814/b264814.txt">Table of n, a(n) for n = 1..10000</a> %e A264814 11 is in the sequence because 111211 is prime. %e A264814 13 is in the sequence because 131413 is prime. %e A264814 15 is not in the sequence because 151615 = 5 * 30323. %t A264814 Select[Range[800], PrimeQ[FromDigits[Join[IntegerDigits[#], IntegerDigits[# + 1], IntegerDigits[#]]]] &] (* _Alonso del Arte_, Nov 25 2015 *) %o A264814 (PARI) is(n)=isprime(eval(Str(n,n+1,n))) %o A264814 (Magma) [n: n in [1..700] | IsPrime(Seqint(Intseq(n) cat Intseq(n+1) cat Intseq(n)))]; // _Vincenzo Librandi_, Nov 30 2015 %o A264814 (Python) %o A264814 from sympy import isprime %o A264814 def aupto(N): %o A264814 return [k for k in range(1, N+1, 2) if isprime(int(str(k)+str(k+1)+str(k)))] %o A264814 print(aupto(530)) # _Michael S. Branicky_, Jul 09 2021 %Y A264814 Cf. A068659, A068660, A262205. %K A264814 nonn,base %O A264814 1,1 %A A264814 _M. F. Hasler_, Nov 25 2015