OFFSET
0,1
LINKS
Ruud H.G. van Tol, Table of n, a(n) for n = 0..10000
FORMULA
n << a(n) << n^1.6. (The actual upper exponent is log(3)/log(2) = 1.5849625....) - Charles R Greathouse IV, Aug 29 2024
From Ruud H.G. van Tol, Aug 31 2024: (Start)
a(2*n) = 9*n + 3.
a(2*n+1) = 3*a(n) + 3.
a(n) = (3/2)^A085058(n) * (2*n+2) - 3/2. (End)
PROG
(PARI) a(n) = (3/2)^valuation(2*n+2, 2)*(3*n+3)-3/2; \\ Ruud H.G. van Tol, Aug 29 2024
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Aug 11 2003
STATUS
approved