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 A208718 #13 Mar 13 2017 04:23:29 %S A208718 5,9,13,24,38,78,140,306,634,1464,3326,8066,19454,48534,121294,308154, %T A208718 785222,2018548,5203634,13482426,35019010,91251438,238278314, %U A208718 623629333,1635062126,4294493670,11296419934,29757590061,78489973742,207281830814 %N A208718 Number of n-bead necklaces labeled with numbers 1..5 allowing reversal, with no adjacent beads differing by more than 1. %H A208718 Andrew Howroyd, <a href="/A208718/b208718.txt">Table of n, a(n) for n = 1..100</a> %F A208718 a(2n+1) = (1/2) * (A208774(2n+1) + r(n+1)) where r(n) = A057960(n+1). - _Andrew Howroyd_, Mar 03 2017 %F A208718 a(2n) = (1/2) * A208774(2n) + (1/4) * (r(n) + r(n+1)) where r(n) = A057960(n+1). - _Andrew Howroyd_, Mar 03 2017 %e A208718 All solutions for n=3: %e A208718 ..3....1....2....4....5....1....2....2....3....4....1....4....3 %e A208718 ..3....1....2....5....5....1....3....2....4....4....2....4....3 %e A208718 ..4....1....2....5....5....2....3....3....4....5....2....4....3 %Y A208718 Column 5 of A208721. %Y A208718 Cf. A208774, A057960. %K A208718 nonn %O A208718 1,1 %A A208718 _R. H. Hardin_, Mar 01 2012 %E A208718 a(25)-a(30) from _Andrew Howroyd_, Mar 03 2017