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 A034594 #11 Aug 13 2024 22:54:15 %S A034594 3,27,33,39,47,51,53,61,63,91,111,123,129,131,143,173,189,199,211,217, %T A034594 219,231,233,237,257,273,279,301,319,341,353,357,417,423,429,473,481, %U A034594 489,493,501,519,523,529,531,537,551,561,573,579,587,597,607,609,619 %N A034594 Concatenation of nextprime(a(n)) and a(n) is a prime. %H A034594 Andrew Howroyd, <a href="/A034594/b034594.txt">Table of n, a(n) for n = 1..10000</a> %e A034594 a(n)=27 -> nextprime(a(n)) is 29 so '2927' is a prime. %o A034594 (PARI) isok(n)=isprime(fromdigits(concat(digits(nextprime(n+1)), digits(n)))) \\ _Andrew Howroyd_, Aug 13 2024 %Y A034594 See also A034591-A034596, A030459. %K A034594 nonn,base %O A034594 1,1 %A A034594 _Patrick De Geest_, Oct 15 1998 %E A034594 Offset changed by _Andrew Howroyd_, Aug 13 2024