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A004744 Numbers n such that binary expansion does not contain 011. 9
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 13, 14, 15, 16, 17, 18, 20, 21, 24, 25, 26, 28, 29, 30, 31, 32, 33, 34, 36, 37, 40, 41, 42, 48, 49, 50, 52, 53, 56, 57, 58, 60, 61, 62, 63, 64, 65, 66, 68, 69, 72, 73, 74, 80, 81, 82, 84, 85, 96, 97, 98, 100, 101, 104, 105 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Index entries for 2-automatic sequences.

MATHEMATICA

Select[Range[0, 110], !MemberQ[Partition[IntegerDigits[#, 2], 3, 1], {0, 1, 1}]&] (* Harvey P. Dale, Oct 15 2013 *)

PROG

(PARI) is(n)=n=binary(n); for(i=3, #n, if(n[i]&&n[i-1]&&!n[i-2], return(0))); 1 \\ Charles R Greathouse IV, Mar 26 2013

(PARI) is(n)=while(n>10, if(bitand(n, 7)==3, return(0)); n>>=1); 1 \\ Charles R Greathouse IV, Feb 11 2017

(Haskell)

a004744 n = a004744_list !! (n-1)

a004744_list = filter f [0..] where

   f x  = x < 4 || x `mod` 8 /= 3 && f (x `div` 2)

-- Reinhard Zumkeller, Jul 01 2013

CROSSREFS

Cf. A007088; A003796 (no 000), A004745 (no 001), A004746 (no 010), A003754 (no 100), A004742 (no 101), A004743 (no 110), A003726 (no 111).

Sequence in context: A004775 A231238 A231239 * A171987 A072226 A247809

Adjacent sequences:  A004741 A004742 A004743 * A004745 A004746 A004747

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified February 16 12:48 EST 2019. Contains 320163 sequences. (Running on oeis4.)