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Numbers whose maximal base-2 run length is 3.
5

%I #13 Jul 08 2021 00:47:53

%S 7,8,14,17,23,24,28,29,34,35,39,40,46,49,55,56,57,58,59,68,69,70,71,

%T 72,78,81,87,88,92,93,98,99,103,104,110,113,114,115,116,117,118,119,

%U 136,137,138,139,140,141,142,145,151,152,156,157,162,163,167,168,174

%N Numbers whose maximal base-2 run length is 3.

%H Michael S. Branicky, <a href="/A037970/b037970.txt">Table of n, a(n) for n = 1..10000</a>

%o (Python)

%o def ok(n):

%o b = bin(n)[2:]

%o return ("000" in b or "111" in b) and not ("0000" in b or "1111" in b)

%o print(list(filter(ok, range(175)))) # _Michael S. Branicky_, Jul 08 2021

%Y Cf. A007088.

%Y Subsequence of A136037.

%K nonn,base

%O 1,1

%A _Clark Kimberling_

%E a(55) and beyond from _Michael S. Branicky_, Jul 08 2021