Pyramidal Number

A pyramidal number is a figurate number that represents a pyramid with a base and a given number of sides. The term is most often used to refer to square pyramidal numbers, which have four sides, but it can also refer to:

  • Triangular pyramidal number (three sides)
  • Square pyramidal number (four sides)
  • Pentagonal pyramidal number (five sides)
  • Hexagonal pyramidal number (six sides)
  • Heptagonal pyramidal number (seven sides)

The formula for a r-gonal pyramid number is:

Famous quotes containing the word number:

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