A133523 - OEIS

%I #13 Feb 22 2018 05:58:13

%S 1,2,4,7,11,16,22,34,54,86,136,212,324,498,772,1202,1873,2915,4524,

%T 7012,10873,16877,26213,40716,63227,98154,152353,236493,367150,570034,

%U 885032,1374048,2133185,3311680,5141292,7981842,12391897,19238551,29867908

%N Number of length n binary sequences with at most 2 of every adjacent 6 bits set.

%H R. H. Hardin, <a href="/A133523/b133523.txt">Table of n, a(n) for n = 0..215</a>

%F Empirical: a(n) = a(n-1) + a(n-3) + 2*a(n-6) - 2*a(n-9) - a(n-10) - a(n-12) + a(n-15). - _R. H. Hardin_, Apr 29 2012.

%F Empirical g.f.: (1 + x + 2*x^2 + 2*x^3 + 2*x^4 + x^5 - 3*x^6 - 3*x^7 - 4*x^8 - 2*x^9 - x^10 + x^12 + x^13 + x^14) / ((1 - x)*(1 + x + x^2)*(1 - x - x^4 - 2*x^6 - x^7 + x^12)). - _Colin Barker_, Feb 22 2018

%K nonn

%O 0,2

%A _R. H. Hardin_, Dec 24 2007