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%I #6 Oct 11 2019 15:09:34
%S 6,7,8,12,15,19,23,24,28,29,33,37,38,40,42,43,44,46,47,49,50,54,55,56,
%T 57,58,64,67,70,71,72,75,77,82,83,84,85,88,90,93,94,95,96,97,102,104,
%U 106,107,109,110,111,112,116,120,122,125,126,129,132,135,136,138,139
%N Numbers n such that 3^n has even digit sum.
%t Select[Range[140], Mod[ Plus @@ IntegerDigits[3^# ], 2] == 0 &] (* _Ray Chandler_, Jun 10 2006 *)
%t Select[Range[150],EvenQ[Total[IntegerDigits[3^#]]]&] (* _Harvey P. Dale_, Mar 12 2013 *)
%Y Cf. A118730, A118734.
%K base,nonn
%O 1,1
%A _Zak Seidov_, May 22 2006