This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A173024 #12 Apr 14 2023 10:54:06 %S A173024 0,7,14,15,28,30,31,56,60,62,63,112,119,120,124,126,127,224,231,238, %T A173024 239,240,247,248,252,254,255,448,455,462,463,476,478,479,480,487,494, %U A173024 495,496,503,504,508,510,511,896,903,910,911,924,926,927,952,956,958,959 %N A173024 Numbers having neither isolated ones nor isolated double ones in their binary representations. %C A173024 Intersection of A144795 and A173025. %C A173024 If m is a term then 2*m is also a term. %C A173024 If m is an odd term then 2*m+1 is also a term. %H A173024 Harvey P. Dale, <a href="/A173024/b173024.txt">Table of n, a(n) for n = 1..1000</a> %F A173024 A173021(a(n+1)) = A173021(a(n)) + 1. %t A173024 nioQ[n_]:=Min[Length/@Select[Split[IntegerDigits[n,2]],FreeQ[#,0]&]]>2; Select[ Range[ 0,1000],nioQ] (* _Harvey P. Dale_, Jan 12 2023 *) %Y A173024 Cf. A005251, A144795, A173021. %K A173024 base,nonn %O A173024 1,2 %A A173024 _Reinhard Zumkeller_, Feb 07 2010