View source for E(2,1)(z)=cosh(sqrt(z))

==Theorem==
The following formula holds:
$$E_{2,1}(z)=\cosh(\sqrt{z}),$$
where $E_{2,1}$ denotes the [[Mittag-Leffler]] function and $\cosh$ denotes [[cosh]].

==Proof==

==References==
* {{PaperReference|Mittag-Leffler Functions and Their Applications|2011|H.J. Haubold|author2=A.M. Mathai|author3=R.K. Saxena|prev=E (0,1)(z)=1/(1-z) for abs(z) less than 1|next=E(2,1)(z)=cosh(sqrt(z))}}: $(2.1)$ (uses notation $E_1$ instead of $E_{1,1}$)

[[Category:Theorem]]
[[Category:Unproven]]