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A121539
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Numbers n such that the binary expansion of n ends in an even number of 1's.
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19
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0, 2, 3, 4, 6, 8, 10, 11, 12, 14, 15, 16, 18, 19, 20, 22, 24, 26, 27, 28, 30, 32, 34, 35, 36, 38, 40, 42, 43, 44, 46, 47, 48, 50, 51, 52, 54, 56, 58, 59, 60, 62, 63, 64, 66, 67, 68, 70, 72, 74, 75, 76, 78, 79, 80, 82, 83, 84, 86, 88, 90, 91, 92, 94, 96, 98, 99, 100
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| Equivalently, increasing sequence defined by: "if n appears a*n+b does not", case a(1)=0, a=2, b=1.
Every even number ends with zero 1's and zero is even, so every even number is a member.
Consists of all even numbers together with A131323.
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FORMULA
| A010060(a(n))+A010060(a(n)+1)=1. [From Vladimir Shevelev (shevelev(AT)bgu.ac.il), Jun 16 2009]
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EXAMPLE
| 11 in binary is 1011, which ends with two 1's.
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MATHEMATICA
| s={2}; With[{a=2, b=1}, Do[If[FreeQ[s, (n-b)/a], AppendTo[s, n]], {n, 3, 100}]]; s
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CROSSREFS
| Cf. A121538, A121540, A121541, A121542.
Sequence in context: A160256 A151545 A097274 * A122138 A047418 A026508
Adjacent sequences: A121536 A121537 A121538 * A121540 A121541 A121542
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KEYWORD
| nonn
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AUTHOR
| Zak Seidov (zakseidov(AT)yahoo.com), Aug 08 2006
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EXTENSIONS
| Edited by N. J. A. Sloane (njas(AT)research.att.com) at the suggestion of Stefan Steinerberger, Dec 17 2007
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