A035808 - OEIS

A035808

Coordination sequence for lattice D*_46 (with edges defined by l_1 norm = 1).

1, 92, 4232, 129812, 2987792, 55053260, 846141848, 11160045188, 128975126048, 1327092434748, 12312430500520, 104062494360052, 808072815510832, 5806722035765932, 38851092934042552, 243319195759791460, 1433080081936088128

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OFFSET

0,2

COMMENTS

Starts to differ from A035741 at a(23). - R. J. Mathar, Oct 24 2008

LINKS

Table of n, a(n) for n=0..16.

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 (46, -1035, 15180, -163185, 1370754, -9366819, 53524680, -260932815, 1101716330, -4076350421, 13340783196, -38910617655, 101766230790, -239877544005, 511738760544, -991493848554, 1749695026860, -2818953098830, 4154246671960, -5608233007146, 6943526580276, -7890371113950, 8233430727600, -7890371113950, 6943526580276, -5608233007146, 4154246671960, -2818953098830, 1749695026860, -991493848554, 511738760544, -239877544005, 101766230790, -38910617655, 13340783196, -4076350421, 1101716330, -260932815, 53524680, -9366819, 1370754, -163185, 15180, -1035, 46, -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=46.

CROSSREFS

Sequence in context: A248451 A017808 A035741 * A017755 A157838 A145416

Adjacent sequences: A035805 A035806 A035807 * A035809 A035810 A035811

KEYWORD

nonn

AUTHOR

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

STATUS

approved