A004748 Binary expansion contains 101.

5, 10, 11, 13, 20, 21, 22, 23, 26, 27, 29, 37, 40, 41, 42, 43, 44, 45, 46, 47, 52, 53, 54, 55, 58, 59, 61, 69, 74, 75, 77, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 101, 104, 105, 106, 107, 108, 109, 110, 111, 116, 117, 118, 119, 122

Offset

1,1

Links

Indranil Ghosh, Table of n, a(n) for n = 1..50000

Index entries for 2-automatic sequences.

Formula

a(n) ~ n. - Charles R Greathouse IV, Oct 23 2015

Example

20 is in the sequence because 20 = 10100_2. '10100' has '101' as one of its substrings. - Indranil Ghosh, Feb 11 2017

Mathematica

Select[Range[200], MemberQ[Partition[IntegerDigits[#, 2], 3, 1], {1, 0, 1}] &] (* Vincenzo Librandi, Feb 17 2018 *)
Select[Range[200], SequenceCount[IntegerDigits[#, 2], {1, 0, 1}]>0&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jun 01 2020 *)

Prog

(Python)
i=j=0
while j<=100:
    if "101" in bin(i)[2:]:
        print(str(j)+" "+str(i))
        j+=1
    i+=1 # Indranil Ghosh, Feb 11 2017
(PARI) is(n)=while(n>4, if(bitand(n, 7)==5, return(1)); n>>=1); 0 \\ Charles R Greathouse IV, Feb 11 2017

Crossrefs

Cf. A004749, A004750, A004751, A004752, A004753.

Sequence in context: A173901 A016084 A007618 * A038030 A094016 A116033

Adjacent sequences: A004745 A004746 A004747 * A004749 A004750 A004751

Keyword

nonn,base,easy

Author

N. J. A. Sloane

Extensions

Offset corrected by Charles R Greathouse IV, Feb 11 2017

Status

approved