%I #7 Nov 24 2015 10:43:26
%S 1,2,4,8,13,26,40,80,121,242,364,728,1093,2186,3280,6560,9841,19682,
%T 22143,22145,22146,22147,22159,22160,22161,22163,22170,22172,22173,
%U 22174,22177,22178,22182,22183,22285,22286,22290
%N Numbers n such that number of runs in the base 3 representation of n is congruent to 1 mod 9.
%t Select[Range[25000],Mod[Length[Split[IntegerDigits[#,3]]],9]==1&] (* _Harvey P. Dale_, Nov 24 2015 *)
%K nonn,base
%O 1,2
%A _Clark Kimberling_