The amazing identity
for all ,
where
is the gamma function. Equating coefficients of
,
,
and
gives some amazing identities for the hyperbolic
secant.
The amazing identity
for all ,
where
is the gamma function. Equating coefficients of
,
,
and
gives some amazing identities for the hyperbolic
secant.
Weisstein, Eric W. "Ramanujan Cos/Cosh Identity." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/RamanujanCosCoshIdentity.html