# Definition:Heptagonal Pyramidal Number

## Definition

Heptagonal pyramidal numbers are those denumerating a collection of objects which can be arranged in the form of a heptagonal pyramid.

The $n$th heptagonal pyramidal number $Q_n$ is defined as:

$\displaystyle Q_n = \sum_{k \mathop = 1}^n H_k$

where $H_k$ is the $k$th heptagonal number.

### Sequence

The sequence of heptagonal pyramidal numbers begins as follows:

$0, 1, 8, 26, 60, 115, 196, 308, 456, 645, 880, 1166, 1508, 1911, 2380, \ldots$

## Also see

• Results about heptagonal pyramidal numbers can be found here.