OFFSET
0,1
COMMENTS
Conjecture: a(n) is the number of letters (0's and 1's) in the n-th iteration of the mapping 00->001, 1->000, starting with 00; see A286939.
LINKS
Clark Kimberling, Table of n, a(n) for n = 0..3000
Index entries for linear recurrences with constant coefficients, signature (1,2,-1,-1,2,0,-2).
FORMULA
G.f.: (2 + x - x^2 - 3*x^5 - 2*x^6)/(1 - x - 2*x^2 + x^3 + x^4 - 2*x^5 + 2 x^7) = (2 + x - x^2 - 3*x^5 - 2*x^6)/((1 - x)*(1 + x)*(1 - x + x^2)*(1 - 2*x^2 - 2*x^3)).
MATHEMATICA
LinearRecurrence[{1, 2, -1, -1, 2, 0, -2}, {2, 3, 6, 10, 17, 29, 51}, 40]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jun 05 2017
STATUS
approved