OFFSET
0,2
COMMENTS
LINKS
Clark Kimberling, Table of n, a(n) for n = 0..2000
Index entries for linear recurrences with constant coefficients, signature (1, 0, 1, 1)
FORMULA
a(n) = a(n-1) + a(n-3) + a(n-4), where a(0) = 1, a(1) = 2, a(2) = 1, a(3) = 3.
G.f.: (-1 - x + x^2 - x^3)/( (x^2+x-1)*(1+x^2)).
MATHEMATICA
LinearRecurrence[{1, 0, 1, 1}, {1, 2, 1, 3}, 100]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Nov 27 2017
STATUS
approved