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A107911
Numbers having consecutive zeros and also consecutive ones in binary representation.
1
12, 19, 24, 25, 28, 35, 38, 39, 44, 48, 49, 50, 51, 52, 56, 57, 60, 67, 70, 71, 75, 76, 77, 78, 79, 83, 88, 89, 92, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 108, 112, 113, 114, 115, 116, 120, 121, 124, 131, 134, 135, 139, 140, 141, 142, 143, 147, 150, 151, 152
OFFSET
1,1
COMMENTS
Intersection of A004753 and A004780; complement of A107909.
MATHEMATICA
czcoQ[n_]:=Module[{c2=Partition[IntegerDigits[n, 2], 2, 1]}, MemberQ[c2, {0, 0}]&&MemberQ[c2, {1, 1}]]; Select[Range[200], czcoQ] (* Harvey P. Dale, Jul 24 2012 *)
PROG
(Python)
def ok(n): b = bin(n)[2:]; return "00" in b and "11" in b
print([k for k in range(153) if ok(k)]) # Michael S. Branicky, Dec 19 2021
CROSSREFS
Sequence in context: A337424 A056688 A342071 * A143800 A344444 A231290
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, May 28 2005
EXTENSIONS
Offset changed to 1 by Michael S. Branicky, Dec 19 2021
STATUS
approved