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 A351361 #14 Mar 13 2022 19:32:00 %S A351361 0,0,0,1,2,3,5,9,17,33,63,124,241,475,930,1831,3593,7077,13905,27377, %T A351361 53847,106006,208601,410723,808514,1592123,3135085,6174695,12161761, %U A351361 23957945,47198847,92997768,183253045,361145269,711793554,1403055509,2765913617 %N A351361 Number of binary necklaces with n beads and at least four consecutive black beads. %H A351361 Marko R. Riedel et al., <a href="https://math.stackexchange.com/questions/4376420/">Necklaces made of black and white beads</a>, Math StackExchange, Feb 2022. %F A351361 a(n) = A000031(n) - A280218(n). %Y A351361 Cf. A351356, A351357, A351358, A351359, A351360. %K A351361 nonn %O A351361 1,5 %A A351361 _Marko Riedel_, Feb 08 2022