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Number of graphical partitions of simple Eulerian graphs (partitions given by the degrees of vertices of simple (no loops or multiple edges) graphs having only vertices of even degrees) having n edges.
1

%I #6 May 25 2024 23:47:48

%S 1,0,0,1,1,1,2,3,3,5,8,10,13,16,22,29,36,45,61,74,95,118,152,183,232,

%T 279,354,422,524,627,780,926,1134,1355,1651,1958,2366,2809,3372,3988,

%U 4757,5628,6678,7874,9283,10964,12861,15130,17686,20799,24209,28389

%N Number of graphical partitions of simple Eulerian graphs (partitions given by the degrees of vertices of simple (no loops or multiple edges) graphs having only vertices of even degrees) having n edges.

%H Sean A. Irvine, <a href="/A069831/b069831.txt">Table of n, a(n) for n = 0..100</a>

%H Sean A. Irvine, <a href="https://github.com/archmageirvine/joeis/blob/master/src/irvine/oeis/a069/A069831.java">Java program</a> (github)

%e a(1)=a(2)=0 since Eulerian graphs having 1 or 2 edges are not simple. The triangle is the unique Eulerian graph having 3 edges and no isolated vertices, thus showing a(3)=1.

%Y Cf. A000569.

%K nonn

%O 0,7

%A _Roland Bacher_, Apr 23 2002