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A003754 Numbers with no 2 adjacent 0's in binary expansion. 15
0, 1, 2, 3, 5, 6, 7, 10, 11, 13, 14, 15, 21, 22, 23, 26, 27, 29, 30, 31, 42, 43, 45, 46, 47, 53, 54, 55, 58, 59, 61, 62, 63, 85, 86, 87, 90, 91, 93, 94, 95, 106, 107, 109, 110, 111, 117, 118, 119, 122, 123, 125, 126, 127, 170, 171, 173, 174, 175, 181 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Theorem (J.-P. Allouche, J. Shallit, G. Skordev): This sequence = A052499 - 1.

A104326(n) = A007088(a(n)); A023416(a(n)) = A087116(a(n)); A107782(a(n)) = 0; A107345(a(n)) = 1; A107359(n) = a(n+1)-a(n); A104326(n) = A007088(a(n)); a(A001911(n)) = A000225(n); a(A000071(n+2)) = A000975(n). - Reinhard Zumkeller, May 25 2005

REFERENCES

David Garth and Adam Gouge, Affinely Self-Generating Sets and Morphisms, Journal of Integer Sequences, Vol. 10 (2007), Article 07.1.5.

LINKS

T. D. Noe, Table of n, a(n) for n=1..1000

J.-P. Allouche, J. Shallit and G. Skordev, Self-generating sets, integers with missing blocks and substitutions, Discrete Math. 292 (2005) 1-15.

MAPLE

Contribution from R. J. Mathar, Oct 23 2010: (Start)

isA003754 := proc(n) local bdgs ; bdgs := convert(n, base, 2) ; for i from 2 to nops(bdgs) do if op(i, bdgs)=0 and op(i-1, bdgs)= 0 then return false; end if; end do; return true; end proc:

A003754 := proc(n) option remember; if n= 1 then 0; else for a from procname(n-1)+1 do if isA003754(a) then return a; end if; end do: end if; end proc: (End)

MATHEMATICA

Select[ Range[0, 200], !MatchQ[ IntegerDigits[#, 2], {___, 0, 0, ___}]&] (* From Jean-François Alcover, Oct 25 2011 *)

PROG

(Haskell)

a003754 n = a003754_list !! (n-1)

a003754_list = filter f [0..] where

   f x = x == 0 || x `mod` 4 > 0 && f (x `div` 2)

-- Reinhard Zumkeller, Dec 07 2012, Oct 19 2011

CROSSREFS

Complement of A004753.

Cf. A023705.

Cf. A196168.

Sequence in context: A087007 A047586 A103841 * A087006 A144147 A068422

Adjacent sequences:  A003751 A003752 A003753 * A003755 A003756 A003757

KEYWORD

nonn,easy,nice

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified June 19 05:13 EDT 2013. Contains 226390 sequences.