cp's OEIS Frontend

A159878 The digits of Pi whose spellings in English contain no i's.

%I A159878 #9 Aug 01 2015 10:11:42
%S A159878 3,1,4,1,2,3,7,3,2,3,4,2,4,3,3,3,2,7,0,2,4,1,7,1,3,3,7,1,0,2,0,7,4,4,
%T A159878 4,2,3,0,7,1,4,0,2,2,0,2,0,3,4,2,3,4,2,1,1,7,0,7,2,1,4,0,1,3,2,2,3,0,
%U A159878 4,7,0,3,4,4,0,0,2,2,3,1,7,2,3,4,0,1,2,4,1,1,1,7,4,0,2,4,1,0,2,7,0,1,3,2,1
%N A159878 The digits of Pi whose spellings in English contain no i's.
%C A159878 Blind Pi: The series of digits of Pi A000796 after removal of any 5, 6, 8 or 9 (see A095763, A089589).
%C A159878 The difference of the value of this constant to Pi is 0.000355..., compared to a difference of 0.0012... = A003077 for 22/7.
%C A159878 The only other alpha language that has no numbers 0 to 9 with an i is Albanian.
%C A159878 It is natural to ask "is the constant defined in this way irrational, transcendental?"
%e A159878 Pi = 3.1415... . The digit 5 or five contains an i in the spelling. So 5 is not in the sequence.
%t A159878 Flatten[ RealDigits[Pi, 10, 174][[1]] /. {5 -> {}, 6 -> {}, 8 -> {}, 9 -> {}}] (* _Robert G. Wilson v_, May 27 2009 *)
%o A159878 (PARI) blindpi(n) =
%o A159878 {
%o A159878 default(realprecision,1000);
%o A159878 local(pi,x);
%o A159878 pi=Vec(Str(Pi*10^99));
%o A159878 default(realprecision,28);
%o A159878 for(x=1,n,
%o A159878 if(pi[x]=="0"||pi[x]=="1"||pi[x]=="2"||pi[x]=="3"||pi[x]=="4"||pi[x]=="7",
%o A159878 print1(pi[x]",");
%o A159878 );
%o A159878 );
%o A159878 }
%K A159878 base,word,nonn
%O A159878 1,1
%A A159878 _Cino Hilliard_, Apr 25 2009
%E A159878 Edited by _R. J. Mathar_, Apr 28 2009