Question 69
Show that for each integer $n$,
$$
\frac{1}{1+n}\binom{4n+1}{2n}
$$
is an integer.
$$
\frac{1}{1+n}\binom{4n+1}{2n}
$$
is an integer.
MathNet 2009-part-01 — 175 problems (EN–VI) Question 69
Math Olympiad Vault · MathNet 2009-part-01 — 175 problems (EN–VI)