OFFSET
1,2
COMMENTS
LINKS
Tero Harju, Combinatorics on Words - From N. J. A. Sloane, Aug 02 2012
T. Harju and D. Nowotka, Border correlation of binary words.
FORMULA
a(n) < 2^(n-1)
a(n) <= F(n) + F(n-2) - m where F(i) is the i-th Fibonacci number and m=2 if n is in the set {2i | i >= 0} - {2^j, 3x2^j | j >= 0}. - Dirk Nowotka (nowotka(AT)utu.fi), May 16 2004
a(n) seems to be asymptotic to phi^n where phi=(1+sqrt(5))/2.
CROSSREFS
KEYWORD
nonn
AUTHOR
Benoit Cloitre, based on the Harju and Nowotka paper, Mar 10 2004
EXTENSIONS
More terms from Dirk Nowotka (nowotka(AT)utu.fi), May 16 2004
a(31)-a(38) from Lars Blomberg, Jan 17 2019
STATUS
approved