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%I #19 Oct 18 2019 21:33:13
%S 25,35,45,60,80,95,118,126,131,136,154,155,175,178,179,183,186,202,
%T 205,212,216,218,231,258,277,283,308,310,316,318,323,361,363,365,373,
%U 378,396,402,428,438,446,454,460,473,485,495,504,508,512,517,536,560,593
%N Starting index of a string of 2 or more consecutive equal digits in decimal expansion of Pi.
%C Digits 3,1,4,... are indexed 1,2,3,...
%C A095916(a(n)) = 0. - _Reinhard Zumkeller_, Mar 12 2015
%C See A049518 for the "exactly 2" variant, which differs from a(11) on. - _M. F. Hasler_, Oct 18 2019
%H Reinhard Zumkeller, <a href="/A049514/b049514.txt">Table of n, a(n) for n = 1..1000</a>
%H <a href="/index/Ph#Pi314">Index entries for sequences related to the number Pi</a>
%e From _M. F. Hasler_, Oct 18 2019: (Start)
%e The integer part of Pi*10^25 ends in 33, i.e., at position 25 starts the (first) string of two repeated digits 3, therefore a(1) = 25.
%e At position 154 starts a string of three '1's, so this sequence lists both, 154 and 155, but sequence A049518 lists none of these. (End)
%t ConsecutiveOccurrences1[alist_, n_] := Flatten @ Position[ Apply[ SameQ, Partition[ alist, n, 1], {1}], True]; ConsecutiveOccurrences1[ First[ RealDigits[Pi, 10, 601]], 2]
%t Flatten[Position[Partition[RealDigits[Pi,10,1000][[1]],2,1],_?(#[[1]] == #[[2]]&),{1},Heads->False]] (* _Harvey P. Dale_, Dec 21 2014 *)
%t SequencePosition[RealDigits[Pi,10,1000][[1]],{x_,x_}][[All,1]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Mar 30 2019 *)
%o (Haskell)
%o a049514 n = a049514_list !! (n-1)
%o a049514_list = filter ((== 0) . a095916) [1..]
%o -- _Reinhard Zumkeller_, Mar 12 2015
%o (PARI) A049514_upto(N=999)={default(realprecision,N); my(p=digits(Pi\10^-N)); select(i->p[i]==p[i+1], [9..N-1])} \\ _M. F. Hasler_, Oct 18 2019
%Y Cf. A049515, A049516, A049517, A049518, A049519, A049520, A049521, A049522, A049523.
%Y Cf. A000796, A095916.
%K nonn,base
%O 1,1
%A _Harvey P. Dale_
%E Edited by _Robert G. Wilson v_, May 09 2003
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