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 A261442 #6 Aug 20 2015 15:38:40 %S A261442 0,2,6,15,32,64,120,218,385,668,1142,1933,3245,5415,8992,14876,24534, %T A261442 40362,66263,108597,177714,290454,474195,773433,1260447,2052608, %U A261442 3340437,5433105,8832176,14351131,23309037,37844339,61423189,99662849,161665292,262176955 %N A261442 Number of binary strings of length n+6 such that the smallest number whose binary representation is not visible in the string is 6. %H A261442 Alois P. Heinz, <a href="/A261442/b261442.txt">Table of n, a(n) for n = 0..1000</a> %H A261442 <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (4,-4,-2,4,-1,2,-2,-1,1). %F A261442 a(n) = A261019(n+6,6). %F A261442 G.f.: (x^2+2*x-2)*x/((x+1)*(x^2+x-1)*(x^3+x-1)*(x-1)^3). - _Alois P. Heinz_, Aug 19 2015 %o A261442 (Haskell) %o A261442 a261442 n = a261019' (n + 6) 6 %Y A261442 Column k=6 of A261019. %K A261442 nonn,easy %O A261442 0,2 %A A261442 _Reinhard Zumkeller_, Aug 18 2015 %E A261442 More terms from _Alois P. Heinz_, Aug 19 2015