In mathematics, this concept refers to a specific relationship within power series expansions of trigonometric functions, particularly the tangent function. It involves the Bernoulli numbers and provides a connection between these numbers and specific values of the Riemann zeta function. For instance, it allows one to express /6 as the infinite sum of the reciprocals of the squares of natural numbers.
This mathematical idea offers a valuable tool for understanding the interplay between seemingly disparate mathematical concepts. Historically, its discovery provided a crucial link in developing the theory of special functions and contributed significantly to advancements in number theory and analysis. It continues to be relevant in modern mathematics, appearing in areas like complex analysis and the study of special values of L-functions.