# [seqfan] Displaying an o.g.f for binomial(mn,n)

Thomas Copeland tccopeland at gmail.com
Fri May 25 13:34:05 CEST 2012

Dear OEIS editors,

Could someone please show me how to format the LaTeX expression below
acceptably for the OEIS?

It represents an apparent o.g.f. (z>=0) for the sequence
binomial(4n,n), A005810. (It's integral is related to the associated
Fuss-Catalan/Raney sequence A002293.)  I'd like to submit similar
expressions for binomial(mn,n) for m=2,3, ....

Please paste the following expression in the LaTeX editor at
http://www.codecogs.com/latex/eqneditor.php to display it:

o.g.f.(z^3)=\frac{1}{2\sqrt\Delta}\sum_{i= 1}^{4}\prod_{j,k\neq
i,j<k}^{4}|x_j-x_k|

where the x_k are the four zeros for   x^4-x+z=0 and delta is the
discriminant |256-27z^3|^(1/2).

Sincerely,
Tom Copeland