A266395 Number of orbits of Aut(Z^7) as function of the infinity norm n of the representative lattice point of the orbit, when the cardinality of the orbit is equal to 161280.

0, 0, 0, 0, 15, 75, 225, 525, 1050, 1890, 3150, 4950, 7425, 10725, 15015, 20475, 27300, 35700, 45900, 58140, 72675, 89775, 109725, 132825, 159390, 189750, 224250, 263250, 307125, 356265, 411075, 471975, 539400, 613800, 695640, 785400, 883575, 990675, 1107225

Offset

1,5

Links

Colin Barker, Table of n, a(n) for n = 1..1000

Index entries for linear recurrences with constant coefficients, signature (5,-10,10,-5,1).

Formula

From Colin Barker, Dec 29 2015: (Start)

a(n) = 5*(n-1)*(n-2)*(n-3)*(n-4)/8 = 15*A000332(n-1).

a(n) = 5*a(n-1)-10*a(n-2)+10*a(n-3)-5*a(n-4)+a(n-5) for n>5.

G.f.: 15*x^5 / (1-x)^5.

(End)

Prog

(PARI) concat(vector(4), Vec(15*x^5/(1-x)^5 + O(x^50))) \\ Colin Barker, May 05 2016

Crossrefs

Number of orbits of Aut(Z^7) as function of the infinity norm A000579, A154286, A102860, A002412, A045943, A115067, A008586, A008585, A005843, A001477, A000217.

Sequence in context: A296193 A135916 A211812 * A260550 A051880 A007328

Adjacent sequences: A266392 A266393 A266394 * A266396 A266397 A266398

Keyword

nonn,easy

Author

Philippe A.J.G. Chevalier, Dec 29 2015

Status

approved