A118730 Numbers n such that 2^n has even digit sum.

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

Robert Israel, Table of n, a(n) for n = 1..10000

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

Cf. A118733, A118734.

Sequence in context: A215618 A189708 A127590 * A291669 A097384 A067886

Adjacent sequences: A118727 A118728 A118729 * A118731 A118732 A118733

Keyword

base,nonn

Author

Zak Seidov, May 22 2006

Status

approved