A035797 Coordination sequence for lattice D*_24 (with edges defined by l_1 norm = 1).

1, 48, 1152, 18448, 221952, 2141808, 17282432, 120037968, 733189632, 4003707568, 19804348032, 89694733968, 375299336448, 1461956877552, 5337746984832, 18374985313488, 59954658388992, 186275979152688, 553339789891712, 1577125278862608, 4326312626433792

Offset

0,2

Links

Table of n, a(n) for n=0..20.

Joan Serra-Sagrista, Enumeration of lattice points in l_1 norm, Inf. Proc. Lett. 76 (1-2) (2000) 39-44.

Index entries for linear recurrences with constant coefficients, signature (24, -276, 2024, -10626, 42504, -134596, 346104, -735471, 1307504, -1961256, 2496144, -2704156, 2496144, -1961256, 1307504, -735471, 346104, -134596, 42504, -10626, 2024, -276, 24, -1).

Formula

a(m) = (Sum_{k=0..n} 2^k*binomial(n, k)*binomial(m-1, k-1)) + 2^n*binomial((n+2*m)/2-1, n-1); with n=24.

Crossrefs

Sequence in context: A287991 A290403 A035719 * A213442 A161693 A162193

Adjacent sequences: A035794 A035795 A035796 * A035798 A035799 A035800

Keyword

nonn

Author

N. J. A. Sloane, J. Serra-Sagrista (jserra(AT)ccd.uab.es)

Status

approved