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Where A124579 has two successive identical values.
2

%I #4 Mar 30 2012 17:31:21

%S 1,9,15,31,36,40,47,165,237,330,354,357,365,402,406,421,426,794,797,

%T 813,885,894,897,905,914,1257,1281,1290,1298,1301,1337,1522,1526,1545,

%U 1842,1865,2094,2098,2118,2121,2137,2569,3598,4602,4609,4621,4629,4726,4729

%N Where A124579 has two successive identical values.

%C Except for a(2), a(5) & a(6) none of these duplicates involve zeros.

%H Robert G. Wilson v, <a href="/A124580/b124580.txt">Table of n, a(n) for n=1..9066</a>

%e Interval 10^n . # of -1 ...# of 0 . # of 1 # of terms

%e ............0.........0.........0.........1........1

%e ............1.........4.........3.........3........1

%e ............2........30........39........31........5

%e ............3.......303.......392.......305.......18

%e ............4......3053......3917......3030.......57

%e ............5.....30421.....39206.....30373......189

%e ............6....303857....392074....304069......636

%e ............7...3039127...3920709...3040164.....1176

%e ............8..30395383..39207306..30397311.....4621

%e ............9.303963673.392072876.303963451....15952

%t p = q = y = z = a = 0; s = {}; Do[ q = Switch[ MoebiusMu@n, -1, y++, 0, z++, 1, a++ ]; If[p == q, AppendTo[s, n - 1]]; p = q, {n, 5000}]; s

%Y Cf. A124579, Column 2 = A063035, Column 1 + Column 3 = A053462.

%K nonn

%O 1,2

%A _Robert G. Wilson v_, Nov 05 2006, Nov 12 2006