| Number | Infinity |
|---|---|
| Parentsequence | Polyhedral numbers |
| Formula | (2n+1)\,(5n^2+5n+1) |
| First terms | 1, 33, 155, 427, 909, 1661 |
| Oeis | A005904 |
| Oeis name | Centered dodecahedral |
In mathematics, a centered dodecahedral number is a centered figurate number that represents a dodecahedron. The centered dodecahedral number for a specific n is given by
(2n+1)\left(5n^2+5n+1\right)
The first such numbers are: 1, 33, 155, 427, 909, 1661, 2743, 4215, 6137, 8569, … .
Congruence Relations
CDC(n) \equiv 1 \pmod{2}CDC(n) \equiv 1-n \pmod{3}CDC(n) \equiv 2n+1 \pmod{3,5,6,10}