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A365204
Centered icositetrachoral numbers.
2
1, 145, 1009, 3745, 10081, 22321, 43345, 76609, 126145, 196561, 293041, 421345, 587809, 799345, 1063441, 1388161, 1782145, 2254609, 2815345, 3474721, 4243681, 5133745, 6157009, 7326145, 8654401, 10155601, 11844145, 13735009, 15843745, 18186481
OFFSET
1,2
COMMENTS
A icositetrachoral number is a centered figurate number that represents a icositetrachoron, which is a four-dimensional regular polytope composed of 24 cells.
One of the 6 centered regular polichoral (centered pentachoral, centered hexadecachoral, centered octachoral, centered icositetrachoral, centered hexacosichoral and centered hecatonicosachoral) numbers.
LINKS
Eric Weisstein's World of Mathematics, Figurate Number.
Wikipedia, 24-cell.
FORMULA
a(n) = 24*n^4 - 48*n^3 + 48*n^2 - 24*n + 1.
G.f.: x*(1 + 140*x + 294*x^2 + 140*x^3 + x^4)/(1 - x)^5. - Stefano Spezia, Aug 26 2023
MATHEMATICA
Table[24*n^4 - 48*n^3 + 48*n^2 - 24*n + 1, {n, 1, 100}]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved