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 A208534 #6 Dec 03 2021 20:35:36 %S A208534 7,21,70,336,1554,7826,39990,210126,1119790,6047412,32981550, %T A208534 181402676,1004668770,5597460306,31345666730,176319474366, %U A208534 995685849690,5642220380006,32071565263710,182807925027504 %N A208534 Number of n-bead necklaces of 7 colors not allowing reversal, with no adjacent beads having the same color. %e A208534 Some solutions for n=4 %e A208534 ..1....1....2....3....3....1....1....2....1....3....1....3....4....1....1....1 %e A208534 ..3....5....3....5....5....6....3....7....5....7....4....7....7....2....3....5 %e A208534 ..1....7....4....6....3....1....4....4....7....6....3....5....5....4....6....4 %e A208534 ..5....2....3....7....7....6....5....3....6....4....2....4....6....7....2....2 %Y A208534 Column 7 of A208535. %K A208534 nonn %O A208534 1,1 %A A208534 _R. H. Hardin_, Feb 27 2012