Figurate numbers

Centered heptagonal number

A centered heptagonal number is a centered figurate number that represents a heptagon with a dot in the center and all other dots surrounding the center dot in successive heptagonal layers. The centered heptagonal number for n is given by the formula . The first few centered heptagonal numbers are 1, 8, 22, 43, 71, 106, 148, 197, 253, 316, 386, 463, 547, 638, 736, 841, 953 (sequence in the OEIS) (Wikipedia).

Centered heptagonal number
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From playlist GEOMETRY 4 - GEOMETRIC FIGURES

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From playlist Counting (Discrete Math)

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From playlist GEOMETRY 4 - GEOMETRIC FIGURES

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Powered by https://www.numerise.com/ Square numbers

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From playlist Mathematical Games Hosted by Ed Pegg Jr.

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From playlist Platonic Solids

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From playlist IIT Delhi: Nano structured materials-synthesis, properties, self assembly and applications | CosmoLearning.org Materials Science

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Related pages

Prime number | Triangular number | Figurate number | Heptagon | Twin prime | Heptagonal number