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 A153031 #18 Mar 22 2015 14:26:41 %S A153031 1,5,7,9,10,11,14,16,17,18,22,25,26,28,29,30,32,34,40,44,47,48,49,52, %T A153031 54,57,62,64,65,67,74,77,84,87,90,91,92,94,97,100,103,110,112,113,115, %U A153031 116,121,124,131,132,134,136,137,138,140,141,142,143,144,150,157,159,161 %N A153031 Positions of prime digits of Pi. %H A153031 Jens Kruse Andersen, <a href="/A153031/b153031.txt">Table of n, a(n) for n = 1..10000</a> %F A153031 a(n) = A073303(n) + 1. - _Michel Marcus_, May 29 2014 %t A153031 Flatten[Position[ Map[If[PrimeQ[ # ], "*", # ] &, RealDigits[ N[Pi, 100]][[1]]], "*"]] %t A153031 Select[ Range@ 166, PrimeQ[ RealDigits[Pi, 10, 166][[1, # ]]] &] (* _Robert G. Wilson v_, Dec 21 2008 *) %t A153031 Flatten[Position[RealDigits[Pi,10,200][[1]],_?PrimeQ]] (* _Harvey P. Dale_, Mar 22 2015 *) %o A153031 (PARI) \p 1000 %o A153031 p=Vec(Str(Pi/10)); for(n=1, #p-9, if(isprime(eval(p[n+2])), print1(n", "))) \\ _Jens Kruse Andersen_, Jul 23 2014 %Y A153031 Cf. A000796. %K A153031 nonn,base %O A153031 1,2 %A A153031 _Julio Cesar de la Yncera_, Dec 17 2008 %E A153031 More concise Mathematica coding added and sequence extended by _Robert G. Wilson v_, Dec 21 2008