Very nice article.

I always wanted to extend my tutorial[1][2][3] with a 4th part, to make the connection between Euler Gamma function and Riemann Zeta Function.

I will link to your article, it's really well written.

[1] https://mourafiq.com/2015/08/30/extensions-of-the-factorial-...

[2] https://mourafiq.com/2015/09/09/extensions-of-the-factorial-...

[3] https://mourafiq.com/2015/10/09/extensions-of-the-factorial-...