A241979 - OEIS

%I #11 Aug 27 2015 08:50:06

%S 0,1,1,0,0,0,1,0,0,1,1,1,0,1,1,0,0,0,1,0,0,1,1,1,0,1,1,0,0,0,1,0,0,1,

%T 1,1,0,1,1,0,0,0,1,0,0,1,1,1,0,1,1,0,0,0,1,0,0,1,1,1,0,1,1,0,0,0,1,0,

%U 0,1,1,1,0,1,1,0,0,0,1,0,0,1,1,1,0,1,1,0,0,0,1,0,0,1,1,1,0,1,1,0,0,0,1,0,0,1,1,1

%N (0,1) sequence such that lengths of three consecutive runs are always distinct.

%C Periodic with period 12;

%C a(n+6) = 1 - a(n).

%H <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (1, 0, 0, 0, 0, -1, 1).

%e .    a(n): 0, 1, 1, 0, 0, 0, 1, 0, 0, 1, 1, 1, 0, 1, 1, 0, 0, 0, 1, 0, 0

%e .    runs: 0, 11,   000,     1, 00,   111,     0, 11,   000,     1, 00

%e . lengths: 1, 2,    3,       1, 2,    3,       1, 2,    3,       1, 2

%t LinearRecurrence[{1, 0, 0, 0, 0, -1, 1},{0, 1, 1, 0, 0, 0, 1},108] (* _Ray Chandler_, Aug 27 2015 *)

%o (Haskell)

%o a241979 n = a241979_list !! n

%o a241979_list = cycle [0,1,1,0,0,0,1,0,0,1,1,1]

%Y Cf. A010882 (run lengths).

%K nonn

%O 0

%A _Reinhard Zumkeller_, Aug 10 2014

%E Extended by _Ray Chandler_, Aug 27 2015