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 A186207 #5 Mar 30 2012 18:35:54 %S A186207 3,31,379,8861,86183,886183,8861837,98861837,929148091,3098861837, %T A186207 83098861837,183098861837,8618379067153,28724068919291, %U A186207 830988618379067,7906715377675267,12897495334688117,675267450287240689,7675267450287240689,83098861837906715377 %N A186207 The first n-digit prime in the decimal expansion of 1/Pi. %C A186207 1/Pi = 0.31830988618379067153.... %p A186207 Digits := 10000: p0 := evalf(1/Pi)*10:for d from 1 to 20 do: id:=0:for i from %p A186207 0 to 50000 while(id=0) do :q0:=trunc(p0*10^(i+d-1)): x:= irem(q0,10^d): if type(x,prime)=true and length(x)=d then printf(`%d, `,x):id:=1: else fi:od:od: %Y A186207 Cf. A049541 A104841. %K A186207 nonn,base %O A186207 1,1 %A A186207 _Michel Lagneau_, Feb 15 2011