For example, is a Jordan-Polya number, because
it can be written as
.
Jordan-Polya numbers arise in the following simple combinatorial
problem. If groups of
distinct objects are given,
then the number of distinct permutations of the
objects
which maintain objects of the same group adjacent are
, a Jordan-Polya number.
The first Jordan-Polya numbers are 1, 2, 4, 6, 8, 12, 16, 24, 32, 36, 48, 64, 72, 96, 120, 128, 144, 192, 216, 240, 256, 288, 384, 432, 480, 512, 576, 720, 768, 864, 960, 1024, 1152, 1296, 1440, 1536, 1728, 1920 more terms