OFFSET
0,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1).
FORMULA
Row sums from A163657: a(n) = Sum_{m=1..n} (2*m*n + m + n + 8).
a(n) = A163655(n) + 2*n.
G.f.: x*(12 - 13*x + 7*x^2)/(x-1)^4.
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4).
E.g.f.: (1/2)*x*(24 + 11*x + 2*x^2)*exp(x). - G. C. Greubel, Aug 01 2017
MATHEMATICA
CoefficientList[Series[x*(12-13*x+7*x^2)/(x-1)^4, {x, 0, 40}], x] (* or *) LinearRecurrence[{4, -6, 4, -1}, {0, 12, 35, 75}, 50](* Vincenzo Librandi, Mar 06 2012 *)
PROG
(PARI) x='x+O('x^50); concat([0], Vec(x*(12-13*x+7*x^2)/(x-1)^4)) \\ G. C. Greubel, Aug 01 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Aug 02 2009
EXTENSIONS
Edited and a(31) corrected by R. J. Mathar, Aug 05 2009
STATUS
approved