A004753 Numbers whose binary expansion contains 100.

4, 8, 9, 12, 16, 17, 18, 19, 20, 24, 25, 28, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 44, 48, 49, 50, 51, 52, 56, 57, 60, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 88, 89, 92, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105

Offset

1,1

Links

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

Index entries for 2-automatic sequences.

Formula

a(n) ~ n. - Charles R Greathouse IV, Sep 24 2012

Mathematica

Select[Range[110], MemberQ[Partition[IntegerDigits[#, 2], 3, 1], {1, 0, 0}]&] (* Harvey P. Dale, Mar 14 2014 *)

Prog

(Haskell)
a004753 n = a004753_list !! (n-1)
a004753_list = filter f [0..] where
   f 0 = False; f x = x `mod` 4 == 0 || f (x `div` 2)
-- Reinhard Zumkeller, Oct 27 2011
(PARI) is(n)=n=binary(n); for(i=3, #n, if(n[i-2]&&!n[i]&&!n[i-1], return(1))); 0 \\ Charles R Greathouse IV, Sep 24 2012
(PARI) is(n)=while(n>3, if(bitand(n, 7)==4, return(1)); n>>=1); 0 \\ Charles R Greathouse IV, Feb 11 2017

Crossrefs

Complement of A003754.

Subsequence of A247875.

Cf. A004748, A004749, A004750, A004752.

Sequence in context: A359783 A359829 A221865 * A144794 A047462 A020671

Adjacent sequences: A004750 A004751 A004752 * A004754 A004755 A004756

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved