OK just didn't know how much you knew. Try this it uses a second LED connected to pin 10 that fades in the oposite way and does what I told you in the first post.
int value = 0; // variable to keep the actual value
int ledpin = 9; // light connected to digital pin 9
int ledpin2=10; // second LED to fade
int value1=0, value2=0;
long time1, time2;
void setup()
{
time1=millis(); // set time as now
time2=millis();
}
void loop()
{
if(millis()>time1) // fade in (from min to max)
{
analogWrite(ledpin, value1); // sets the value (range from 0 to 255)
time1 = millis()+30; // time delay between each pwm fade in pulse
value1++;
if(value1 > 255)value1=0;
}
if(millis()>time2) // fade out (from max to min)
{
analogWrite(ledpin2, value2);
time2 = millis() +35;
value2= value2 -5;
if(value2 < 0)value2=300;
}
}