%I #5 May 13 2018 10:22:46
%S 2,3,6,22,253,37098,109873815
%N Number of inequivalent Krom functions on n variables (or 3SAT instances) under permuting and complementing variables.
%D Knuth, Donald E., Satisfiability, Fascicle 6, volume 4 of The Art of Computer Programming. Addison-Wesley, 2015, pages 148 and 220, Problem 191.
%Y Cf. A109459.
%K nonn,more
%O 0,1
%A _N. J. A. Sloane_, May 13 2018