Reading a paper regarding Bernoulli numbers, and I stumbled onto a definition.  First let
$$\frac{x}{e^x-1}=\sum_{k=0}^{\infty}B_k\frac{x^k}{k!}$$
The author then goes on to define new terms.
Let
$$\beta_n=(-1)^n\frac{B_n}{n}, n\ge 1$$
noting that $\beta_n=B_n/n$ except for $\beta_1=-B_1=1/2$ since $B_n=0$ when $n$ is odd and greater than 1.  Now he defines
$$\beta_n^{(j)}=\frac1{j!}\sum_{i_1+i_2+...+i_j=n}\binom{n}{i_1,i_2,...,i_j}\beta_{i_1}...\beta_{i_1}$$
I'm not even sure where to start with this, but, I suppose I'm confused about the role of the bound $i_1+i_2+...+i_j=n.$  I would have to say that the sum of the $i_k$'s are integer partitions of a number $n$.  Should I take this as unique integers?  Or is this simply all possible integer partitions of $n$? So for $n=4$, so i take
$$\{4, 3+1, 2+2, 2+1+1, 1+1+1+1\}$$
or 
$$\{4, 3+1, 1+3, 2+2, 2+1+1, 1+2+1, 1+1+2, 1+1+1+1\}$$
And what of the $j$?  So this tells me, for example if $j=2$ that my summation is 
$$\beta_4^{(2)}=\frac{1}{2!}\left[\binom{4}{2,2}\frac{B_2}{2}\frac{B_2}{2}+\binom{4}{3,1}\frac{B_3}{3}\frac{B_1}{1}\right]$$
Or do i have to include the case of $\binom{4}{1,3}$.  Or am i completely off to begin with?


Question: Continuations in Clojure
Answer: A common use of continuations is in the implementation of control structures for: returning from a function, breaking from a loop, exception handling etc. Most languages (like Java, C++ etc) provide these features as part of the core language. Some languages don't (e.g: Scheme). Instead, these languages expose continuatiions as first class objects and let the programmer define new control structures. Thus Scheme should be looked upon as a programming language toolkit, not a complete language in itself.

In Clojure, we almost never need to use continuations directly, because almost all the control structures are provided by the language/VM combination. Still, first class continuations can be a powerful tool in the hands of the competent programmer. Especially in Scheme, continuations are better than the equivalent counterparts in other languages (like the setjmp/longjmp pair in C). This article has more details on this.

BTW, it will be interesting to know how Rich Hickey justifies his opinion about continuations. Any links for that?