8 Lights

const int SER= 8;
const int LATCH=9;
const int CLK = 10;
int ledvals [9]= {0,1,2,4,8,16,32,64,128};
int addlight [9]= {0,1,3,7,15,63,127,255};
int backledvals [9]={128,64,32,16,8,4,2,1,0};

void setup() {
pinMode (SER, OUTPUT);
pinMode (LATCH, OUTPUT);
pinMode (CLK, OUTPUT);
digitalWrite (LATCH, LOW);
shiftOut( SER, CLK, MSBFIRST, B11111111);
digitalWrite (LATCH, HIGH);
delay (200);
digitalWrite (LATCH, LOW);
shiftOut (SER,CLK, MSBFIRST, B00000000);
digitalWrite (LATCH, HIGH);

void rider()

for(int i=0; i<9; i++)
{

digitalWrite (LATCH, LOW);
shiftOut( SER, CLK, MSBFIRST, addlight[i]);
digitalWrite (LATCH, HIGH);
delay (200);
}
for (int j=9; j>0; j--)
{
digitalWrite (LATCH, LOW);
shiftOut( SER, CLK, MSBFIRST, addlight[j]);
digitalWrite (LATCH, HIGH);
delay (200);

}

void accumulate()
void loop()
{
  rider();
}