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A144795
A positive integer n is included if every 1 in binary n is next to at least one other 1.
9
3, 6, 7, 12, 14, 15, 24, 27, 28, 30, 31, 48, 51, 54, 55, 56, 59, 60, 62, 63, 96, 99, 102, 103, 108, 110, 111, 112, 115, 118, 119, 120, 123, 124, 126, 127, 192, 195, 198, 199, 204, 206, 207, 216, 219, 220, 222, 223, 224, 227, 230, 231, 236, 238, 239, 240, 243, 246
OFFSET
1,1
COMMENTS
n is included if A144790(n) >= 2.
A173024 is a subsequence. - Reinhard Zumkeller, Feb 07 2010
LINKS
MAPLE
isA144795 := proc(n) local bind, i ; bind := convert(n, base, 2) ; for i from 1 to nops(bind) do if i = 1 then if op(i, bind) = 1 and op(i+1, bind) = 0 then RETURN(false) : fi; elif i = nops(bind) then if op(i, bind) = 1 and op(i-1, bind) = 0 then RETURN(false) : fi; else if op(i, bind) = 1 and op(i-1, bind) = 0 and op(i+1, bind) = 0 then RETURN(false) : fi; fi; od: RETURN(true) ; end: for n from 3 to 400 do if isA144795(n) then printf("%d, ", n) ; fi; od: # R. J. Mathar, Sep 29 2008
MATHEMATICA
Select[Range@ 250, AllTrue[Map[Length, Select[Split@ IntegerDigits[#, 2], First@ # == 1 &]], # > 1 &] &] (* Michael De Vlieger, Aug 20 2017 *)
CROSSREFS
Complement of A377169.
Sequence in context: A095029 A028792 A325804 * A364292 A077459 A048717
KEYWORD
base,nonn
AUTHOR
Leroy Quet, Sep 21 2008
EXTENSIONS
Extended by R. J. Mathar, Sep 29 2008
STATUS
approved