int Rot=0;
int Gruen=125;
int Blau=250;
int Zeit=60;
int Loop=130;

void setup() {

}

void loop() {
for(int i1=0; i1<Loop; i1++)
{
  Rot++;
  Gruen++;
  Blau--;
  analogWrite(A0, Rot);
  analogWrite(A1, Gruen);
  analogWrite(A2, Blau);
  delay(Zeit);
}
for(int i2=0; i2<Loop; i2++)
{
  Rot++;
  Gruen--;
  Blau--;
  analogWrite(A0, Rot);
  analogWrite(A1, Gruen);
  analogWrite(A2, Blau);
  delay(Zeit);
}
for(int i3=0; i3<Loop; i3++)
{
  Rot--;
  Gruen--;
  Blau++;
  analogWrite(A0, Rot);
  analogWrite(A1, Gruen);
  analogWrite(A2, Blau);
  delay(Zeit);
}
for(int i4=0; i4<Loop; i4++)
{
  Rot--;
  Gruen++;
  Blau++;
  analogWrite(A0, Rot);
  analogWrite(A1, Gruen);
  analogWrite(A2, Blau);
  delay(Zeit);
}
}