# Definition:Bernoulli Numbers/Archaic Form/Definition 2

## Definition

The old form Bernoulli numbers $B_n^*$ are a sequence of rational numbers defined by the exponential generating function:

$\displaystyle 1 - \frac x 2 \cot \frac x 2 = \sum_{n \mathop = 1}^\infty \frac{B_n^* x^{2 n} } {\left({2 n}\right)!}$
 $\displaystyle 1 - \frac x 2 \cot \frac x 2$ $=$ $\displaystyle \sum_{n \mathop = 1}^\infty \frac{B_n^* x^{2 n} } {\left({2 n}\right)!}$ $\displaystyle$ $=$ $\displaystyle \frac{B_1^* x^2} {2!} + \frac{B_2^* x^4} {4!} + \frac{B_3^* x^6} {6!} + \cdots$

for $x \in \R$ such that $\left\lvert{x}\right\rvert < \pi$

### Sequence of Bernoulli Numbers: Archaic Form

The sequence of old style Bernoulli numbers begins:

 $\displaystyle B_1^*$ $=$ $\displaystyle \dfrac 1 6$ $\displaystyle B_2^*$ $=$ $\displaystyle \dfrac 1 {30}$ $\displaystyle B_3^*$ $=$ $\displaystyle \dfrac 1 {42}$ $\displaystyle B_4^*$ $=$ $\displaystyle \dfrac 1 {30}$ $\displaystyle B_5^*$ $=$ $\displaystyle \dfrac 5 {66}$ $\displaystyle B_6^*$ $=$ $\displaystyle \dfrac {691} {2730}$ $\displaystyle B_7^*$ $=$ $\displaystyle \dfrac 7 6$ $\displaystyle B_8^*$ $=$ $\displaystyle \dfrac {3617} {510}$ $\displaystyle B_9^*$ $=$ $\displaystyle \dfrac {43 \, 867} {798}$ $\displaystyle B_{10}^*$ $=$ $\displaystyle \dfrac {174 \, 611} {330}$ $\displaystyle B_{11}^*$ $=$ $\displaystyle \dfrac {854 \, 513} {138}$ $\displaystyle B_{12}^*$ $=$ $\displaystyle \dfrac {236 \, 364 \, 091} {2730}$