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 A043689 #14 Apr 13 2021 23:09:31 %S A043689 42,74,82,84,85,86,90,106,138,146,148,149,150,154,162,164,165,166,168, %T A043689 169,171,172,173,174,178,180,181,182,186,202,210,212,213,214,218,234, %U A043689 266,274,276,277,278,282,290,292,293,294,296 %N A043689 a(n) = (s(n)-1)/2, where s(n) is the n-th number whose base-2 representation has exactly 7 runs. %C A043689 a(n) = A238248(n) - 1. - _Reinhard Zumkeller_, Feb 20 2014 %H A043689 Vincenzo Librandi, <a href="/A043689/b043689.txt">Table of n, a(n) for n = 1..1000</a> %t A043689 (# - 1)/2&/@Select[Range[50], Length[Split[IntegerDigits[#, 2]]]==7&] (* _Vincenzo Librandi_, Feb 22 2014 *) %Y A043689 Cf. A238248. %K A043689 nonn,base %O A043689 1,1 %A A043689 _Clark Kimberling_