A043777 - OEIS

%I #7 May 02 2020 17:14:46

%S 1,2,4,8,13,26,40,80,91,92,96,97,100,101,102,104,121,138,140,141,142,

%T 145,146,150,151,172,173,177,178,181,182,183,185,192,194,195,196,208,

%U 209,210,212,242,253,254,258,259,262,263,264

%N Numbers n such that number of runs in the base 3 representation of n is congruent to 1 mod 4.

%t Select[Range[300],Mod[Length[Split[IntegerDigits[#,3]]],4]==1&] (* _Harvey P. Dale_, May 02 2020 *)

%K nonn,base

%O 1,2

%A _Clark Kimberling_