A345027 - OEIS

%I #19 Mar 13 2022 11:13:49

%S 1,1,6,480,719040,28111985280,39667596799259520,

%T 2716101119587792215121920,11750142295253741381979240922398720,

%U 4059370170952132363824590307446791630779187200,138004666315436722628999805261994204164032807656029840998400,557103455087735168484078548670473120844063643381325957791547628642631680000

%N a(n) is the number of maximal chains of labeled split graphs with n vertices.

%C A split graph is one which can be partitioned into a clique and an independent set.

%C a(n) is the number of sequences G[0], G[1], ..., G[n(n-1)/2] where each G[i] is a split graph with i edges and G[i] is a subgraph of G[i+1] for each i. All graphs are labeled.

%H Brendan McKay, <a href="/A345027/b345027.txt">Table of n, a(n) for n = 1..14</a>

%Y Cf. A345024.

%K nonn,hard

%O 1,3

%A _Brendan McKay_, Jun 06 2021