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%I #23 Feb 20 2018 22:49:18
%S 2,5,26,1072,9340584,6406603624626816,
%T 16879085743296494006611933604867584,
%U 717956902513121252476003434439730271412009640241362775196201481717907456
%N Number of SNPN-equivalence classes of Boolean functions of n or fewer variables.
%C Number of Boolean functions distinct under simultaneous complementation of the inputs and/or permutation of the inputs, complementation of the output. Algorithm includes elements that are conjectural in nature. Documentation of the algorithm is at web link.
%D F. Harary and E. M. Palmer, Graphical Enumeration, Academic Press, NY, 1973.
%H Marko Riedel, <a href="/A299104/b299104.txt">Table of n, a(n) for n = 1..16</a>
%H Marko Riedel et al., <a href="https://math.stackexchange.com/questions/2650624/">Number of boolean functions</a>
%H Marko Riedel, <a href="/A299104/a299104_1.maple.txt">Maple code for sequence including all cycle indices for Power Group Enumeration, computed from first principles and by enumeration.</a>
%Y Cf. A000370, A003180.
%K nonn
%O 1,1
%A _Marko Riedel_, Feb 15 2018