Brocard's problem is a problem in mathematics that asks to find integer values of n and m for which
n
!
+
1
=
m
2
,
{\displaystyle n!+1=m^{2},}
where n! is the factorial. It was posed by Henri Brocard in a pair of articles in 1876 and 1885, and independently in 1913 by Srinivasa Ramanujan.
== Brown numbers ==
Pairs of the numbers (n, m) that solve Brocard's problem are called Brown numbers. There are only three known pairs of Brown numbers:
(4,5), (5,11...