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The digits of Pi whose spellings in English contain no i's.
0

%I #9 Aug 01 2015 10:11:42

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

%C Blind Pi: The series of digits of Pi A000796 after removal of any 5, 6, 8 or 9 (see A095763, A089589).

%C 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 The only other alpha language that has no numbers 0 to 9 with an i is Albanian.

%C It is natural to ask "is the constant defined in this way irrational, transcendental?"

%e Pi = 3.1415... . The digit 5 or five contains an i in the spelling. So 5 is not in the sequence.

%t Flatten[ RealDigits[Pi, 10, 174][[1]] /. {5 -> {}, 6 -> {}, 8 -> {}, 9 -> {}}] (* _Robert G. Wilson v_, May 27 2009 *)

%o (PARI) blindpi(n) =

%o {

%o default(realprecision,1000);

%o local(pi,x);

%o pi=Vec(Str(Pi*10^99));

%o default(realprecision,28);

%o for(x=1,n,

%o if(pi[x]=="0"||pi[x]=="1"||pi[x]=="2"||pi[x]=="3"||pi[x]=="4"||pi[x]=="7",

%o print1(pi[x]",");

%o );

%o );

%o }

%K base,word,nonn

%O 1,1

%A _Cino Hilliard_, Apr 25 2009

%E Edited by _R. J. Mathar_, Apr 28 2009