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 A163674: a(n) = Sum_{m=1..n} (2*m*n + m + n + 9).
G.f.: x*(13 - 15*x + 8*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*(26 + 11*x + 2*x^2)*exp(x). - G. C. Greubel, Aug 02 2017
MATHEMATICA
CoefficientList[Series[x*(13-15*x+8*x^2)/(x-1)^4, {x, 0, 40}], x] (* or *) LinearRecurrence[{4, -6, 4, -1}, {0, 13, 37, 78}, 50] (* Vincenzo Librandi, Mar 06 2012 *)
PROG
(PARI) x='x+O('x^50); concat([0], Vec(x*(13 -15*x +8*x^2)/(x-1)^4)) \\ G. C. Greubel, Aug 02 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Aug 03 2009
EXTENSIONS
Edited and a(31) corrected by R. J. Mathar, Aug 05 2009
STATUS
approved