function g = p25_g ( n, x )

%*****************************************************************************80
%
%% p25_g evaluates the gradient for problem 25.
%
%  Licensing:
%
%    This code is distributed under the MIT license.
%
%  Modified:
%
%    31 December 2000
%
%  Author:
%
%    John Burkardt
%
%  Input:
%
%    integer N, the number of variables.
%
%    real X(N), the values of the variables.
%
%  Output:
%
%    real G(N), the gradient of the objective function.
%
  g = zeros ( n, 1 );

  for i = 1 : n
    g(i) = i * 4.0 * x(i)^3;
  end

  return
end
