A144795 A positive integer n is included if every 1 in binary n is next to at least one other 1.

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

Author

Leroy Quet, Sep 21 2008

Keywords

• base
• nonn

Comments

n is included if A144790(n) >= 2.

A173024 is a subsequence. - Reinhard Zumkeller, Feb 07 2010

Links

• Michael De Vlieger, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A144790, A144794.

Cf. A004760, A173022, A005251, A173025. - Reinhard Zumkeller, Feb 07 2010

Complement of A377169.

Programs

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 *)

Extensions

Extended by R. J. Mathar, Sep 29 2008