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A129117 Numbers that appear exactly five times in A101402. (Also indices of fives in A101403.). 3

%I

%S 727,2181,3635,5089,6543,7997,9451,10905,12358,13812,15266,16720,

%T 18174,19628,21082,22536,23989,25443,26897,28351,29805,31259,32713,

%U 34167,35620,37074,38528,39982,41436,42890,44344,45798,47250,48704,50158

%N Numbers that appear exactly five times in A101402. (Also indices of fives in A101403.).

%C It is also interestng to look at this sequence modulo 727.

%H Reinhard Zumkeller, <a href="/A129117/b129117.txt">Table of n, a(n) for n = 1..1000</a>

%F A101403(a(n)) = 5.

%e a(1) = 727 since A101402(2045) = A101402(2046) = A101402(2047) = A101402(2048) = A101402(2049) = 727.

%e a(1) = 727 since A101403(727) = 5.

%t A101402[0] = 0; A101402[1] = 1; A101402[n_] := A101402[n] = A101402[2^(Floor[Log[2, n - 1]])] + A101402[n - 1 - 2^(Floor[Log[2, n - 1]])]; TheList = Table[A101402[i], {i, 0, 203000}]; TheList2 = Union[TheList]; A101403 = Table[Count[TheList, i], {i, 0, Last[TheList]}]; TheSeq = Delete[Union[Table[ If[TheList[[i]] == TheList[[i + 4]], TheList[[i]]], {i, 1, Length[TheList] - 4}]], -1] Count[A101403, 5] Length[TheSeq]

%o (Haskell)

%o import Data.List (elemIndices)

%o a129117 n = a129117_list !! (n-1)

%o a129117_list = elemIndices 5 a101403M_list

%o -- _Reinhard Zumkeller_, Aug 28 2014

%Y Cf. A101402, A101403.

%K easy,nonn

%O 1,1

%A Keith Schneider (schneidk(AT)email.unc.edu), May 25 2007

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Last modified April 6 15:41 EDT 2020. Contains 333276 sequences. (Running on oeis4.)