OFFSET
1,2
COMMENTS
Values 1 and 2 appear alternately and each time in runs whose lengths are the powers of 3. Each power of 3 is used twice: once for a run of 1's and then for a run of 2's.
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
FORMULA
a(n) = floor(n/(3^floor(log(n)/log(3)))).
From Robert Israel, Mar 15 2017: (Start)
a(3n) = a(3n+1) = a(3n+2) = a(n).
G.f.: g(x) satisfies g(x) = x + 2 x^2 + (1+x+x^2) g(x^3). (End)
EXAMPLE
a(1) = 1/(3^0) = 1.
MAPLE
seq( evalf(floor(n/ (3^floor(log[3](n))))), n=1..500);
MATHEMATICA
Table[IntegerDigits[n, 3][[1]], {n, 110}] (* or *) Table[{PadRight[{}, 3^k, 1], PadRight[ {}, 3^k, 2]}, {k, 0, 4}]//Flatten (* Harvey P. Dale, Mar 12 2023 *)
CROSSREFS
KEYWORD
easy,nonn,base
AUTHOR
Peter C. Heinig (algorithms(AT)gmx.de), Oct 20 2006
EXTENSIONS
Name changed by Franklin T. Adams-Watters, Sep 29 2011
STATUS
approved