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 A242827 #20 Oct 21 2014 03:08:32
%S A242827 7,71,71428571,7142857142857,7142857142857142857142857142857
%N A242827 Primes formed by the initial digits of the decimal expansion of 1/14, starting at the first nonzero digit in the expansion.
%C A242827 a(6) has 104 digits. - _Michel Marcus_, May 26 2014
%o A242827 (PARI) lista(nn) = {v = [7,1,4,2,8,5]; n = 0; for (i=0, nn, n = 10*n+ v[(i % 6)+1]; if (ispseudoprime(n), print1(n, ", ")););} \\ _Michel Marcus_, May 26 2014
%Y A242827 Cf. A021018.
%Y A242827 Corresponding sequences for 1/k: A242824 (k=7), A093676 (k=12), A242826 (k=13), A242828 (k=17), A242833 (k=19).
%K A242827 nonn,base
%O A242827 1,1
%A A242827 _Felix Fröhlich_, May 23 2014