3 | bounce

float
  y = 50,
  step = 5.0,
  gravity = 0.2;
int repeat = 10;

void setup () {
    size(1280, 747);
    noStroke();
}

void draw () {
    background(0);
    y += step;
    step += gravity;
    if (y > height) {
        step *= -0.9;
        --repeat;
    }
    if (repeat < 0)
        noLoop();
    fill(255);
    circle(width/2, y, 50);
}