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 A101219 #10 Jul 01 2025 16:02:26 %S A101219 353,3511,3517,3529,3541,3547,3559,3571,3583,35107,35149,35227,35251, %T A101219 35257,35281,35311,35317,35353,35401,35419,35449,35461,35491,35509, %U A101219 35521,35569,35593,35617,35677,35797,35809,35839,35863,35911,35977 %N A101219 Primes that are a concatenation of 3, 5 and a prime. %H A101219 Harvey P. Dale, <a href="/A101219/b101219.txt">Table of n, a(n) for n = 1..1000</a> %H A101219 Peter Alfeld <a href="http://www.math.utah.edu/~alfeld/math/p10000.html">The 10,000 smallest prime numbers</a>. %e A101219 3511 is a prime concatenated from the primes 3, 5 and 11. %t A101219 Select[35*10^IntegerLength[#]+#&/@Prime[Range[200]],PrimeQ] (* _Harvey P. Dale_, Jan 23 2019 *) %Y A101219 Cf. A100607, A101218, A101249, A101250, A101251, A101252. %K A101219 nonn,base,easy %O A101219 1,1 %A A101219 _Parthasarathy Nambi_, Dec 14 2004 %E A101219 Extended by _Ray Chandler_, Dec 22 2004