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%I M4310 #19 Dec 18 2017 22:45:05
%S 6,480,196560,149869440,208166112000,470619551001600,
%T 1622357050938624000,8100931274981056512000,
%U 56279222605087617687552000,526611567858781597240688640000,6462027944190599588931310387200000,101691538301880025620001692844032000000
%N Number of 3-edge-colored connected trivalent graphs with 2n labeled nodes.
%D R. C. Read, Some Enumeration Problems in Graph Theory. Ph.D. Dissertation, Department of Mathematics, Univ. London, 1958.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H Andrew Howroyd, <a href="/A006713/b006713.txt">Table of n, a(n) for n = 2..50</a>
%H R. C. Read, <a href="/A002831/a002831.pdf">Letter to N. J. A. Sloane, Feb 04 1971</a> (gives initial terms of this sequence)
%Y Cf. A006712 (for not necessarily connected graphs), A248362 (for the incorrect values). See also A002830, A002831, A002851.
%K nonn
%O 2,1
%A _N. J. A. Sloane_
%E a(5)-a(6) corrected and a(7)-a(10) from _Sean A. Irvine_, Oct 05 2014
%E Terms a(11) and beyond from _Andrew Howroyd_, Dec 18 2017
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