A043693 Numbers whose base-4 representation has an even number of runs.

4, 6, 7, 8, 9, 11, 12, 13, 14, 16, 20, 22, 23, 26, 31, 32, 37, 40, 41, 43, 47, 48, 53, 58, 60, 61, 62, 64, 68, 70, 71, 72, 73, 75, 76, 77, 78, 80, 84, 86, 87, 90, 95, 97, 98, 99, 100, 102, 103, 106, 108, 109, 110, 113, 114, 115, 116, 118

Offset: 1

Author

Clark Kimberling

Keywords

• nonn
• base

Programs

Mathematica

Select[Range[120],EvenQ[Length[Split[IntegerDigits[#,4]]]]&] (* Harvey P. Dale, Oct 19 2018 *)