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A092181 Figurate numbers based on the 24-cell (4-D polytope with Schlaefli symbol {3,4,3}). 7
1, 24, 153, 544, 1425, 3096, 5929, 10368, 16929, 26200, 38841, 55584, 77233, 104664, 138825, 180736, 231489, 292248, 364249, 448800, 547281, 661144, 791913, 941184, 1110625, 1301976, 1517049, 1757728, 2025969, 2323800, 2653321, 3016704 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

This is the 4-dimensional regular convex polytope called the 24-cell, hyperdiamond or icositetrachoron.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Hyun Kwang Kim, On Regular Polytope Numbers.

Eric Weisstein's World of Mathematics, 24-Cell

Index to sequences with linear recurrences with constant coefficients, signature (5,-10,10,-5,1). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jun 21 2010]

FORMULA

a(n)=n^2*((3*n^2)-(4*n)+2)

a(n) = C(n+3,4) + 19 C(n+2,4) + 43 C(n+1,4) + 9 C(n,4)

a(n)= +5*a(n-1) -10*a(n-2) +10*a(n-3) -5*a(n-4) +a(n-5). G.f.: x*(1+19*x+43*x^2+9*x^3)/(1-x)^5. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jun 21 2010]

EXAMPLE

a(3)= 3^2*((3*3^2)-(4*3)+2) = 9*(27-12+2) = 9*17 = 153

PROG

(MAGMA) [n^2*((3*n^2)-(4*n)+2): n in [1..40]]; // Vincenzo Librandi, May 22 2011

CROSSREFS

Cf. A000332, A000583, A014820, A092182, A092183.

Sequence in context: A042118 A039494 A159650 * A001702 A004308 A008663

Adjacent sequences:  A092178 A092179 A092180 * A092182 A092183 A092184

KEYWORD

easy,nonn

AUTHOR

Michael J. Welch (mjw1(AT)ntlworld.com), Mar 31 2004

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Last modified February 13 04:08 EST 2012. Contains 205435 sequences.