OFFSET
1,1
COMMENTS
FORMULA
a(n) = g(n,0,0) with g(n,m,k) = if n=0 then k else if k=3^m-1 then g(n-1,m,3*(k+1)/2+1) else g(n-1,m,k+1).
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Oct 19 2007
STATUS
approved