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A118730
Numbers n such that 2^n has even digit sum.
3
1, 2, 3, 6, 9, 11, 13, 14, 15, 17, 21, 26, 32, 33, 36, 37, 41, 42, 43, 44, 45, 46, 47, 50, 51, 54, 55, 57, 58, 60, 61, 64, 65, 67, 70, 71, 73, 74, 76, 77, 78, 79, 80, 82, 83, 84, 85, 86, 90, 91, 95, 98, 102, 103, 106, 107, 112, 113, 115, 116, 117, 120, 122, 123, 124, 126
OFFSET
1,2
LINKS
MAPLE
filter:= proc(n) convert(convert(2^n, base, 10), `+`)::even end proc:
select(filter, [$1..1000]); # Robert Israel, Apr 12 2021
MATHEMATICA
Select[Range[126], Mod[ Plus @@ IntegerDigits[2^# ], 2] == 0 &] (* Ray Chandler, Jun 10 2006 *)
CROSSREFS
Sequence in context: A215618 A189708 A127590 * A291669 A097384 A067886
KEYWORD
base,nonn
AUTHOR
Zak Seidov, May 22 2006
STATUS
approved