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%I #27 Mar 05 2023 19:43:55
%S 1,1,2,6,23,105,552,3276,21632,157058,1241542,10599358,97078720,
%T 948631866,9844060930,108045790170,1249891268947,15192207346713,
%U 193489732812832,2575819322454708,35763019798305487,516830453606687539,7760160395056532042,120860540786892879030
%N Row sums of A352366.
%C a(n) is the number of chordal graphs with fixed symmetric perfect elimination ordering; i.e., graphs on V = [n] such that 1,...,n and n,...,1 are perfect elimination orderings. - _Robert Lauff_, Jan 25 2023
%C a(n) is the number of labeled unit-interval-graphs. This is because connected labeled unit-interval-graphs are a Catalan family. Given a partition of [n], we draw a connected unit-interval-graph for each of the partition classes. This weights the partitions with a Catalan number. The connection to my previous comment can be shown by induction. - _Robert Lauff_, Feb 01 2023
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Chordal_graph#Perfect_elimination_and_efficient_recognition">Chordal graph</a>.
%Y Cf. A000108, A352366.
%K nonn
%O 0,3
%A _Peter Luschny_, Mar 15 2022
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