A338152 - OEIS

%I #13 Oct 13 2020 14:30:38

%S 1,2,24,24024,193270310,767795414400

%N a(n) is the number of acyclic orientations of the edges of an n-dimensional demihypercube.

%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/HalvedCubeGraph.html">Halved Cube Graph</a>

%F a(n) = |Sum_{k=0..2^(n-1)} (-1)^k * A334280(n, k)|.

%t Table[Abs[ChromaticPolynomial[GraphData[{"HalvedCube",n}]][-1]],{n,1,6}]

%Y Cf. A137888, A290060, A295174, A334280.

%Y Cf. A033815 (cross-polytope), A058809 (wheel), A334247 (hypercube), A338153 (prism), A338154 (antiprism).

%K nonn,more

%O 1,2

%A _Peter Kagey_, Oct 13 2020