%I #10 May 19 2023 19:59:06

%S 1,4,7,13,16,19,28,31,49,52,55,61,64,67,76,79,112,115,124,127,193,196,

%T 199,205,208,211,220,223,241,244,247,253,256,259,268,271,304,307,316,

%U 319,448,451,460,463,496,499,508,511,769,772

%N Numbers whose base-4 representation contains exactly one 1 and no 2's.

%t Select[Range[800],DigitCount[#,4,1]==1&&DigitCount[#,4,2]==0&] (* _Harvey P. Dale_, Jan 11 2013 *)

%Y Cf. A007090.

%K nonn,base

%O 1,2

%A _Clark Kimberling_