A228700 a(n) = 2^n*(4^n-3^(n+1)+3*2^n-1)/6.

0, 0, 0, 8, 160, 2080, 22400, 217728, 1989120, 17461760, 149248000, 1252354048, 10373242880, 85129175040, 693959884800, 5629506387968, 45504088637440, 366845229137920, 2951654132940800, 23714655581503488, 190326054636748800, 1526262396511846400, 12232027326644224000, 97987805132628164608, 784692030546598952960

Offset

0,4

Links

Table of n, a(n) for n=0..24.

J. Brandts and C. Cihangir, Counting triangles that share their vertices with the unit n-cube, in Conference Applications of Mathematics 2013 in honor of the 70th birthday of Karel Segeth. Jan Brandts, Sergey Korotov, et al., eds., Institute of Mathematics AS CR, Prague 2013.

Index entries for linear recurrences with constant coefficients, signature (20,-140,400,-384).

Formula

G.f.: 8*x^3 / ((2*x-1)*(4*x-1)*(6*x-1)*(8*x-1)). - Colin Barker, Sep 06 2013

Mathematica

Table[2^n*(4^n - 3^(n + 1) + 3*2^n - 1)/6, {n, 0, 24}] (* Amiram Eldar, Oct 08 2020 *)

Crossrefs

Sequence in context: A201030 A127369 A364741 * A036909 A369539 A221077

Adjacent sequences: A228697 A228698 A228699 * A228701 A228702 A228703

Keyword

nonn,easy

Author

N. J. A. Sloane, Sep 05 2013

Status

approved