OFFSET
1,4
LINKS
Index entries for linear recurrences with constant coefficients, signature (0,7,0,-6).
FORMULA
a(n+1) = 3*a(n) if n is odd, a(n+1) = 2*a(n)+1 if n is even.
a(n) = f(3^f(n/2) * 2^f((n-1)/2) / 5), where f = floor.
G.f.: (x^2 (1 + 3 x))/((-1 + x) (1 + x) (-1 + 6 x^2)).
a(n) = 7*a(n-2) - 6*a(n-4).
MATHEMATICA
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Nov 10 2019
STATUS
approved