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Centered pentagonal number

From Wikipedia, the free encyclopedia

A centered pentagonal number is a centered figurate number that represents a pentagon with a dot in the center and all other dots surrounding the center in successive pentagonal layers. The centered pentagonal number for n is given by the formula

The first few centered pentagonal numbers are

1, 6, 16, 31, 51, 76, 106, 141, 181, 226, 276, 331, 391, 456, 526, 601, 681, 766, 856, 951, 1051, 1156, 1266, 1381, 1501, 1626, 1756, 1891, 2031, 2176, 2326, 2481, 2641, 2806, 2976 (sequence A005891 in the OEIS).

The parity of centered pentagonal numbers follows the pattern odd-even-even-odd, and in base 10 the units follow the pattern 1-6-6-1.

YouTube Encyclopedic

  • 1/3
    3 646
    45 239
    6 812
  • ✪ Polygonal Number - Formula to find nth Polygonal Number - Derivation
  • ✪ Beautiful visualization | Sum of first n Hex numbers = n^3 | animation
  • ✪ How to show diagonals in a cube


See also

External links

  • Weisstein, Eric W. "Centered pentagonal number". MathWorld.
This page was last edited on 20 May 2019, at 04:44
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