int a = 0;
void setup() {
  // put your setup code here, to run once:
pinMode(9, OUTPUT);
pinMode(10, OUTPUT);
pinMode(11, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
for (a = 0; a <= 225; a = a+10){      //red
  analogWrite(9,a);
  delay(100);
}
for (a = 225; a >= 0; a = a-10){
  analogWrite(9,a);
  delay(100);
}

for (a = 0; a <= 225; a = a+10){    //green
  analogWrite(10,a);
  delay(100);
}
for (a = 225; a >= 0; a = a-10){
  analogWrite(10,a);
  delay(100);
}

for (a = 0; a <= 225; a = a+10){     //blue
  analogWrite(11,a);
  delay(100);
}
for (a = 225; a >= 0; a = a-10){
  analogWrite(11,a);
  delay(100);
}

for (a = 0; a <= 225; a = a+10){     //r+g (yellow)
  analogWrite(9,a);
  analogWrite(10,a);
  delay(100);
}
for (a = 225; a >= 0; a = a-10){
  analogWrite(9,a);
  analogWrite(10,a);
  delay(100);
}

for (a = 0; a <= 225; a = a+10){     //purple
  analogWrite(9,a);
  analogWrite(11,a);
  delay(100);
}
for (a = 225; a >= 0; a = a-10){
  analogWrite(9,a);
  analogWrite(11,a);
  delay(100);
}

for (a = 0; a <= 225; a = a+10){     //b+g (turquoise)
  analogWrite(11,a);
  analogWrite(10,a);
  delay(100);
}
for (a = 225; a >= 0; a = a-10){
  analogWrite(11,a);
  analogWrite(10,a);
  delay(100);
}

for (a = 0; a <= 225; a = a+10){     //white
  analogWrite(9,a);
  analogWrite(10,a);
  analogWrite(11,a);
  delay(100);
}
for (a = 225; a >= 0; a = a-10){
  analogWrite(9,a);
  analogWrite(10,a);
  analogWrite(11,a);
  delay(100);
}
}