OFFSET
0,2
COMMENTS
Presumably a(n) ~ 3*n - floor(n*sqrt(2)) = A195176(n). In the first hundred, a(n) = A195176(n) except for n = 41, 70, 82, 94 where a(n) = A195176(n) - 1.
The conjecture is false; A195176(n) - a(n) increases without bound (though not monotonically) since log_2(3) < 3 - sqrt(2). - Charles R Greathouse IV, Jan 15 2012
Basically a duplicate of A020914. - R. J. Mathar, Jan 16 2012
FORMULA
a(n) = ceiling( n * log_2(3) ). - Charles R Greathouse IV, Jan 15 2012
MAPLE
for n from 0 to 120 do : for k from 0 to 100 do: x:=floor(2^k /3^n):if x=1 then printf(`%d, `, k):else fi:od:od:
PROG
(PARI) a(n)=ceil(n*log(3)/log(2)) \\ Charles R Greathouse IV, Jan 15 2012
CROSSREFS
KEYWORD
nonn
AUTHOR
Michel Lagneau, Jan 15 2012
STATUS
approved