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%I #40 Feb 05 2024 10:48:38
%S 1,3,22,513,67685,37205801,74992370359,543437207831908,
%T 14224090440652751128,1355263603548588163939892,
%U 473629305416562052216063601182,611217587951920565260750675133929534,2929826971690847578421964010597063713803102,52431093582529289457516130655642218612938867242516
%N Number of colorings of the edges of the complete graph on n unlabeled vertices using at most four colors up to permutation of the colors.
%D Harary and Palmer, Graphical Enumeration, Chapter Six.
%H Marko Riedel, <a href="/A233748/b233748.txt">Table of n, a(n) for n = 2..40</a>
%H Marko Riedel, <a href="http://math.stackexchange.com/questions/607956/">Colorings of the cube</a>.
%H Marko Riedel, <a href="/A233748/a233748_1.maple.txt">Colorings of the complete graph Kn with some number of swappable colors</a>.
%Y Cf. A007869.
%K nonn
%O 2,2
%A _Marko Riedel_, Dec 20 2013
%E Definition clarified by _Andrew Howroyd_, Feb 04 2024