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Troughs in digital expansions of Pi: digits which are smaller than their neighbors.
1

%I #10 Oct 01 2016 16:55:52

%S 1,1,2,3,7,2,4,2,2,0,1,1,3,3,0,0,4,2,0,1,0,2,0,2,0,2,3,0,1,0,1,2,2,0,

%T 4,0,3,0,0,1,2,3,0,1,4,4,0,0,0,3,0,4,4,0,1,2,0,5,5,1,4,5,4,2,6,1,2,1,

%U 0,0,1,4,5,2,0,0,2,4,1,3,0,2,0,1,1,3,2,0,1,1,4,1,0,0,2,2,2,0,1,1,3,3,2

%N Troughs in digital expansions of Pi: digits which are smaller than their neighbors.

%H Harvey P. Dale, <a href="/A105273/b105273.txt">Table of n, a(n) for n = 1..10000</a>

%F d[i]<d[i+1]&&d[i]<d[i-1]

%t Transpose[Select[Partition[RealDigits[Pi,10,500][[1]],3,1],Sign[ Differences[ #]]=={-1,1}&]][[2]] (* _Harvey P. Dale_, Dec 24 2014 *)

%K nonn,base

%O 1,3

%A _Zak Seidov_, Apr 25 2005