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 A330022 #14 Nov 29 2019 08:32:18 %S A330022 0,2,4,8,12,22,32 %N A330022 Length of shortest binary string containing, as contiguous blocks, all palindromes of length n. %C A330022 Greedy supersequence algorithms give the upper bounds a(7) <= 60, a(8) <= 74, a(9) <= 142, a(10) <= 180, a(11) <= 344, a(12) <= 410, a(13) <= 798. Probably some of these are tight. The value for a(6) was computed by checking all 8! arrangements of the 8 palindromes of length 3, optimizing overlaps. Probably someone with more computing power could compute a(7) (resp., a(8)) by checking all 16! = 20922789888000 arrangements of the palindromes of length 7 (resp., 8). %e A330022 The corresponding strings for 1 <= n <= 6 are: %e A330022 1: 01 %e A330022 2: 0011 %e A330022 3: 00010111 %e A330022 4: 000011001111 %e A330022 5: 0000010001010111011111 %e A330022 6: 00000011001111000010010110111111 %Y A330022 Cf. A057148. %K A330022 nonn,more %O A330022 0,2 %A A330022 _Jeffrey Shallit_, Nov 27 2019