
theorem
  for L being continuous lower-bounded LATTICE st L-waybelow is
  multiplicative for p being Element of L st p is pseudoprime holds p is prime
proof
  let L be continuous lower-bounded LATTICE such that
A1: L-waybelow is multiplicative;
  let p be Element of L;
  assume p is pseudoprime;
  then
  for a,b being Element of L st a"/\"b << p holds a <= p or b <= p by A1,Th44;
  hence thesis by A1,Lm3;
end;
