Wronskians of theta functions and series for \(1/\pi\) (Q1789490)

In this interesting paper, the authors used the Jacobi theta functions to define some functions analogous to Ramanujan's function \(f(n)\) defined in his famous paper ``Modular equations and approximation to \(\pi\)'' [Q. J. Math. 45, 350--372 (1914; JFM 45.1249.01)]. They then used these new functions to study Ramanuan's type series for \(1/{\pi}\). Several amazing Ramanuan's type series for \(1/{\pi}\) are derived.