A037978 Numbers whose maximal base 4 run length is 3.

21, 42, 63, 64, 84, 86, 87, 106, 127, 128, 149, 168, 169, 171, 191, 192, 213, 234, 252, 253, 254, 257, 258, 259, 277, 298, 319, 320, 336, 337, 338, 339, 344, 345, 346, 347, 348, 349, 350, 351, 362, 383, 384, 405, 424, 425, 427

Offset: 1

Author

Clark Kimberling

Keywords

• nonn
• base

Crossrefs

Cf. A043278.

Programs

Mathematica

Select[Range[500],Max[Length/@Split[IntegerDigits[#,4]]]==3&] (* Harvey P. Dale, Jul 16 2017 *)