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Numbers having in binary representation at least two ones and two zeros.
4

%I #17 Sep 10 2021 11:33:46

%S 9,10,12,17,18,19,20,21,22,24,25,26,28,33,34,35,36,37,38,39,40,41,42,

%T 43,44,45,46,48,49,50,51,52,53,54,56,57,58,60,65,66,67,68,69,70,71,72,

%U 73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,96,97

%N Numbers having in binary representation at least two ones and two zeros.

%H Reinhard Zumkeller, <a href="/A158581/b158581.txt">Table of n, a(n) for n = 1..10000</a>

%F A023416(a(n)) > 1; A000120(a(n)) > 1.

%t Select[Range[100],Min[DigitCount[#,2]]>1&] (* _Harvey P. Dale_, Mar 09 2013 *)

%o (Python)

%o def ok(n): b = bin(n)[2:]; return b.count('0') >= 2 and b.count('1') >= 2

%o print(list(filter(ok, range(98)))) # _Michael S. Branicky_, Sep 10 2021

%Y Intersection of A158582 and A057716.

%Y Cf. A007088, A000120, A023416

%K nonn,base

%O 1,1

%A _Reinhard Zumkeller_, Apr 16 2009