A167191 4*n*(1+45*n+620*n^2).

2664, 20568, 68592, 161616, 314520, 542184, 859488, 1281312, 1822536, 2498040, 3322704, 4311408, 5479032, 6840456, 8410560, 10204224, 12236328, 14521752, 17075376, 19912080, 23046744, 26494248, 30269472, 34387296, 38862600

Offset

1,1

Comments

See A167190, where this sequence arises as the integer part of the quotient.

Links

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

Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1).

Formula

G.f. 24*x*(111+413*x+96*x^2) / (x-1)^4 . - R. J. Mathar, Jan 27 2012

a(n) = 4*a(n-1) -6*a(n-2) +4*a(n-3) -a(n-4). - Vincenzo Librandi, Jul 02 2012

Mathematica

CoefficientList[Series[24*(111+413*x+96*x^2)/(x-1)^4, {x, 0, 40}], x] (* Vincenzo Librandi, Jul 02 2012 *)
LinearRecurrence[{4, -6, 4, -1}, {2664, 20568, 68592, 161616}, 40] (* Harvey P. Dale, Jun 15 2014 *)

Prog

(Magma)  I:=[2664, 20568, 68592, 161616]; [n le 4 select I[n] else 4*Self(n-1)-6*Self(n-2)+4*Self(n-3)-Self(n-4): n in [1..40]]; // Vincenzo Librandi, Jul 02 2012

Crossrefs

Cf. A167190.

Sequence in context: A235514 A197108 A224685 * A002482 A187293 A187195

Adjacent sequences: A167188 A167189 A167190 * A167192 A167193 A167194

Keyword

nonn,easy

Author

A.K. Devaraj, Oct 30 2009

Extensions

Extended beyond a(6) by R. J. Mathar, Nov 17 2009

Status

approved