OFFSET
1,2
LINKS
Peter J. C. Moses, Table of n, a(n) for n = 1..10000
EXAMPLE
Let n=6, 2*n-1=11 which in binary 1011. Number with double 1's is 1101111 which in decimal 111. Thus a(6)=111/3=37.
MATHEMATICA
Map[#/3^IntegerExponent[#, 3]&[FromDigits[Flatten[IntegerDigits[2#-1, 2]/.{1->{1, 1}}], 2]]&, Range[100]] (* Peter J. C. Moses, Mar 31 2013 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Vladimir Shevelev, Mar 31 2013
STATUS
approved