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Indices of prime digits in the decimal expansion of Pi.
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%I #6 Aug 23 2021 21:48:52

%S 0,4,6,8,9,10,13,15,16,17,21,24,25,27,28,29,31,33,39,43,46,47,48,51,

%T 53,56,61,63,64,66,73,76,83,86,89,90,91,93,96,99,102,109,111,112,114,

%U 115,120,123,130,131,133,135,136,137,139,140,141,142,143,149,156

%N Indices of prime digits in the decimal expansion of Pi.

%H Harvey P. Dale, <a href="/A073303/b073303.txt">Table of n, a(n) for n = 0..10000</a>

%e Pi=3.141592653, so the indices of prime digits are 0,4,6,8,9...

%t Flatten[Position[RealDigits[Pi,10,200][[1]],_?PrimeQ]]-1 (* _Harvey P. Dale_, Oct 01 2013 *)

%Y Cf. A000796, A073264.

%K easy,nonn,base

%O 0,2

%A Y. Kelly Itakura (yitkr(AT)mta.ca), Aug 22 2002

%E More terms from _Harvey P. Dale_, Oct 01 2013