147 (number)
147 (one hundred [and] forty-seven) is the natural number following 146 and preceding 148.
In mathematics
147 is the fourth centered icosahedral number. These are a class of figurate numbers that represent points in the shape of a regular icosahedron or alternatively points in the shape of a cuboctahedron, and are magic numbers for the face-centered cubic lattice.[1] Separately, it is also a magic number for the diamond cubic.[2]
It is also the fourth Apéry number following 19, where[3]
with 147 the composite index of the nineteenth triangle number, 190.[4][5]
There are 147 different ways of representing one as a sum of unit fractions with five terms, allowing repeated fractions,[6] and 147 different self-avoiding polygonal chains of length six using horizontal and vertical segments of the integer lattice.[7]