
theorem Th47:
  for n being non zero Element of NAT, i being Element of
  F_Complex st i is Integer holds eval(unital_poly(F_Complex, n), i) is Integer
proof
  let n be non zero Element of NAT;
  let i be Element of F_Complex such that
A1: i is Integer;
  reconsider j = i as Integer by A1;
  ex y being Element of F_Complex st y = i & eval( unital_poly(F_Complex,n)
  ,y) = (j |^ n) - 1 by Th44;
  hence thesis;
end;
