Icosahedral number

An icosahedral number is a figurate number that represents an icosahedron. The nth icosahedral number is given by the formula

${n(5n^{2}-5n+2) \over 2}$

The first such numbers are 1, 12, 48, 124, 255, 456, 742, 1128, 1629, 2260, 3036, 3972, 5083, … (sequence A006564 in the OEIS).

References

Kim, Hyun Kwang, On Regular Polytope Numbers (PDF), archived from the original (PDF) on 2010-03-07