// so we'll try it a few times before declaring it a failure.
	const attempts = 5
	err := errors.New("!=nil")
	for i := 0; i < attempts && err != nil; i++ {
		delta := Duration(20+i*50) * Millisecond
		if err = testAfterQueuing1(delta, after); err != nil {
			t.Logf("attempt %v failed: %v", i, err)
		}
	}
	if err != nil {
		t.Fatal(err)
	}
}

var slots = []int{5, 3, 6, 6, 6, 1, 1, 2, 7, 9, 4, 8, 0}