Hectagonal number

A hectagonal number is a type of polygonal number, which in turn is a type of figurate number. It is so named because it can be arranged to form a hectagon, which is a 100 sided polygon. If $H\_n$ is the "n"th hectagonal number then $H\_n=n(49n-48)$. The first few hectagonal numbers are:

1, 100, 297, 592, 985, 1476, 2065, 2752, 3537, 4420, 5401, 6480, 7657, 8932, 10305, 11776, 13345, 15012, 16777, 18640.

Since "hectagon" is not the universally agreed upon name for a 100 sided figure, these numbers may go by another name. See article polygon for discussion.