assign(iterate, primes). % The following fixes [+,-,*] as the ring of integers (mod domain_size). set(integer_ring). formulas(assumptions). % Assume that f and g have a ring structure. g(x) = M * x. f(x,y) = (H * x) + (K * y). % Denial of associativity. f(f(a,b),c) != f(a,f(b,c)). end_of_list. formulas(assumptions). % Each of these equations was a candidate for being a single axiom % for group theory. % % We can show that each has a nonassociative model (and therefore % is not a single axiom) by using ring structures. % % The sizes required for these examples range from 11 to 41. % f(f(g(f(y,g(z))),x),f(f(g(f(z,x)),z),y)) = z. % candidate 1 % f(f(x,f(g(x),z)),f(g(f(f(y,x),g(x))),y)) = z. % candidate 64 % f(f(f(x,x),g(x)),g(f(g(f(y,z)),f(y,x)))) = z. % candidate 30 g(f(g(f(y,f(x,z))),f(y,f(f(x,x),g(x))))) = z. % candidate 107 % g(f(g(f(x,f(y,z))),f(f(f(g(x),x),x),y))) = z. % candidate 60 % f(f(y,g(f(z,y))),f(f(z,g(f(x,g(z)))),x)) = z. % candidate 68 % f(f(x,y),f(y,g(f(f(g(f(g(x),z)),y),y)))) = z. % candidate 11 end_of_list.