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%I #11 Feb 21 2024 08:26:08
%S 1,1,2,1,10,3,1,30,44,4,1,70,284,134,5,1,140,1224,1594,329,6,1,252,
%T 4110,11330,6552,700,7,1,420,11616,58432,71484,21822,1344,8,1,660,
%U 28908,241098,534562,347274,62370,2388,9,1,990,65208,842842,3069360,3612924
%N Triangle read by rows: number of P-graphs by number of edges and number of non-root nodes.
%H R. C. Read, <a href="https://doi.org/10.1007/BF02188172">On the enumeration of a class of plane multigraphs</a>, Aequat. Math., 31 (1986), 47-63.
%F Reference gives generating function.
%K tabl,nonn,easy,nice
%O 2,3
%A _N. J. A. Sloane_
%E More terms from Pab Ter (pabrlos(AT)yahoo.com), May 27 2004