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# A Summation of Fractional Factorials

Do not write the answer in the comments below. Rather give hints to the solution of this problem.

$$\displaystyle \sum_{k=0}^n \frac {1}{(n-k)!(n+k)!}$$

Note by Sharky Kesa
3 years, 11 months ago

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Hint: $$(2n)!$$

- 3 years, 11 months ago

Hint:(2n)

- 3 years, 11 months ago

Hint: Common denominator and binomial coefficients

- 3 years, 11 months ago

1/[n(2n!)]

- 3 years, 5 months ago