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%I #40 Apr 11 2021 04:52:31
%S 5,10,11,13,20,21,22,23,26,27,29,37,40,41,42,43,44,45,46,47,52,53,54,
%T 55,58,59,61,69,74,75,77,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,
%U 95,101,104,105,106,107,108,109,110,111,116,117,118,119,122
%N Binary expansion contains 101.
%H Indranil Ghosh, <a href="/A004748/b004748.txt">Table of n, a(n) for n = 1..50000</a>
%H <a href="/index/Ar#2-automatic">Index entries for 2-automatic sequences</a>.
%F a(n) ~ n. - _Charles R Greathouse IV_, Oct 23 2015
%e 20 is in the sequence because 20 = 10100_2. '10100' has '101' as one of its substrings. - _Indranil Ghosh_, Feb 11 2017
%t Select[Range[200], MemberQ[Partition[IntegerDigits[#, 2], 3, 1], {1, 0, 1}] &] (* _Vincenzo Librandi_, Feb 17 2018 *)
%t Select[Range[200],SequenceCount[IntegerDigits[#,2],{1,0,1}]>0&] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jun 01 2020 *)
%o (Python)
%o i=j=0
%o while j<=100:
%o if "101" in bin(i)[2:]:
%o print(str(j)+" "+str(i))
%o j+=1
%o i+=1 # _Indranil Ghosh_, Feb 11 2017
%o (PARI) is(n)=while(n>4,if(bitand(n,7)==5, return(1)); n>>=1); 0 \\ _Charles R Greathouse IV_, Feb 11 2017
%Y Cf. A004749, A004750, A004751, A004752, A004753.
%K nonn,base,easy
%O 1,1
%A _N. J. A. Sloane_
%E Offset corrected by _Charles R Greathouse IV_, Feb 11 2017
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