A162264 a(n) = (2*n^3 + 5*n^2 + 7*n)/2.

7, 25, 60, 118, 205, 327, 490, 700, 963, 1285, 1672, 2130, 2665, 3283, 3990, 4792, 5695, 6705, 7828, 9070, 10437, 11935, 13570, 15348, 17275, 19357, 21600, 24010, 26593, 29355, 32302, 35440, 38775, 42313, 46060, 50022, 54205, 58615, 63258

Offset

1,1

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

Row sums from A154681: a(n) = Sum_{m=1..n} (2*m*n + m + n + 3).

From Vincenzo Librandi, Mar 05 2012: (Start)

G.f.: x*(7 - 3*x + 2*x^2)/(1-x)^4.

a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4). (End)

Mathematica

LinearRecurrence[{4, -6, 4, -1}, {7, 25, 60, 118}, 50] (* or *) CoefficientList[Series[(7-3*x+2*x^2)/(1-x)^4, {x, 0, 40}], x] (* Vincenzo Librandi, Mar 05 2012 *)

Crossrefs

Cf. A154681.

Sequence in context: A110672 A213481 A266709 * A034135 A212136 A213392

Adjacent sequences: A162261 A162262 A162263 * A162265 A162266 A162267

Keyword

nonn,easy

Author

Vincenzo Librandi, Jun 29 2009

Extensions

New name from Vincenzo Librandi, Mar 05 2012

Status

approved