OFFSET
1,1
COMMENTS
m is in the sequence iff the set {1,2,...,2^(2*m-2)} considered in reduced residue system modulo 2*m-1 contains the same number of odd and even integers.
EXAMPLE
5 in the sequence since modulo 2*5-1=9 we have {1,2,4,8,16,32}={1,2,4,8,7,5} and the last set contains 3 odd and 3 even elements.
MATHEMATICA
fQ[n_] := Block[{r = Union@ PowerMod[2, Range[0, 2 n - 2], 2 n - 1]}, Length@ r == 2 Count[ OddQ@ r, True]]; Select[ Range@ 138, fQ] (* Robert G. Wilson v, Aug 26 2010 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Vladimir Shevelev, Jul 14 2010
EXTENSIONS
More terms from Robert G. Wilson v, Aug 26 2010
STATUS
approved