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A118734
Numbers n such that 2^n and 3^n have even digit sum.
9
6, 15, 33, 37, 42, 43, 44, 46, 47, 50, 54, 55, 57, 58, 64, 67, 70, 71, 77, 82, 83, 84, 85, 90, 95, 102, 106, 107, 112, 116, 120, 122, 126, 129, 135, 136, 138, 140, 142, 149, 154, 161, 168, 170, 173, 176, 178, 179, 180, 181, 185, 193, 195, 198, 200, 207, 209, 210, 217
OFFSET
1,1
LINKS
MAPLE
filter:= proc(n) convert(convert(2^n, base, 10), `+`)::even and convert(convert(3^n, base, 10), `+`)::even end proc:
select(filter, [$1..1000]); # Robert Israel, Apr 12 2021
MATHEMATICA
Select[Range[220], And @@ ((Mod[ Plus @@ IntegerDigits[ # ], 2] == 0 &) /@ {2^#, 3^#}) &] (* Ray Chandler, Jun 10 2006 *)
CROSSREFS
Cf. Intersection of A118730 and A118733.
Sequence in context: A121666 A186829 A231452 * A200895 A225278 A213779
KEYWORD
base,nonn
AUTHOR
Zak Seidov, May 22 2006
EXTENSIONS
Extended by Ray Chandler, Jun 10 2006
STATUS
approved