|
|
A164459
|
|
Number of binary strings of length n with no substrings equal to 0001 0011 or 1100.
|
|
1
|
|
|
13, 21, 35, 58, 96, 159, 264, 439, 730, 1215, 2023, 3369, 5612, 9349, 15576, 25952, 43241, 72050, 120054, 200043, 333329, 555423, 925499, 1542157, 2569695, 4281884, 7134907, 11888905, 19810501, 33010271, 55005074, 91655056, 152724992
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
4,1
|
|
LINKS
|
|
|
FORMULA
|
G.f.: -x^4*(13-5*x-7*x^2-12*x^3+6*x^4-4*x^5+8*x^6) / ( (x^5+x^4+2*x^3+x^2-1)*(x-1)^2 ). - R. J. Mathar, Jan 19 2011
a(n) = 2*a(n-1)-2*a(n-4)+a(n-5)-a(n-6)+a(n-7). [Harvey P. Dale, May 06 2011]
|
|
MATHEMATICA
|
LinearRecurrence[{2, 0, 0, -2, 1, -1, 1}, {13, 21, 35, 58, 96, 159, 264}, 40] (*Harvey P. Dale, May 06 2011 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,easy
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|