A centered polygonal number consisting of a central dot with five dots around it, and then additional dots in the gaps between adjacent dots. The general term is , and the first few such numbers are 1, 6, 16, 31, 51, 76, ... (OEIS A005891). The generating function of the centered pentagonal numbers is

# Centered Pentagonal Number

## See also

Centered Polygonal Number, Centered Square Number, Centered Triangular Number, Hex Number, Pentagonal Number## Explore with Wolfram|Alpha

## References

Sloane, N. J. A. Sequence A005891/M4112 in "The On-Line Encyclopedia of Integer Sequences."## Referenced on Wolfram|Alpha

Centered Pentagonal Number## Cite this as:

Weisstein, Eric W. "Centered Pentagonal Number."
From *MathWorld*--A Wolfram Web Resource. https://mathworld.wolfram.com/CenteredPentagonalNumber.html