Definition:Binomial Coefficient/Technical Note
Definition
The $\LaTeX$ code to render the binomial coefficient $\dbinom n k$ can be written in the following ways:
\dbinom n k
or:
\ds {n \choose k}
The \dbinom
form is preferred on $\mathsf{Pr} \infty \mathsf{fWiki}$ because it is simpler.
It is in fact an abbreviated form of \ds \binom n k
, which is the preferred construction when \ds
is required for another entity in the expression.
While the form \binom n k
is valid $\LaTeX$ syntax, it renders the entity in the reduced size inline style: $\binom n k$ which $\mathsf{Pr} \infty \mathsf{fWiki}$ does not endorse.
To render compound arguments, braces are needed to delimit the parameter when using \dbinom
, but (confusingly) not \choose
.
For example, to render $\dbinom {a + b} {c d}$ the following can be used:
\dbinom {a + b} {c d}
or:
\ds {a + b \choose c d}
$\ds {a + b \choose c d}$
Again, for consistency across $\mathsf{Pr} \infty \mathsf{fWiki}$, the \dbinom
form is preferred.