Ramanujan theta function

Proper noun

Meaning

the Ramanujan theta function

(mathematics) A theta function that generalizes the form of the Jacobi theta functions while capturing their general properties. It is defined as:



f
(
a
,
b
)
=

∑

n
=
−
∞


∞



a



n
(
n
+
1
)

2





b



n
(
n
−
1
)

2





{\displaystyle f(a,b)=\sum _{n=-\infty }^{\infty }a^{\frac {n(n+1)}{2}}\;b^{\frac {n(n-1)}{2}}}

for |ab| < 1.

Close letter words and terms