public void WhenSizeGreaterThanZero_ThenReturnSequence(int size, int lastValue)
            {
                var result = Sequencer.Fibonacci(size);

                Assert.That(result.Count, Is.EqualTo(size));
                Assert.That(result.Last(), Is.EqualTo(lastValue));
            }
            public void WhenSizeIsZeroOrLess_ThenReturnEmpty(int size)
            {
                var result = Sequencer.Fibonacci(size);

                Assert.That(result, Is.Empty);
            }