求級數\( \displaystyle \frac{1}{3 \times 7}+\frac{1}{7 \times 11}+\frac{1}{11 \times 15}+\frac{1}{15 \times 19}+\ldots+\frac{1}{(4n-1)\times(4n+3)}+\ldots \)，請各位大大幫忙給出算式，謝謝

忘了給答案，答案是 n/(3(4n+3))

謝謝大大！