OFFSET
1,1
COMMENTS
Row 2 of the convolution array A213771. - Clark Kimberling, Jul 04 2012
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 A154614: a(n) = Sum_{m=1..n} (m*n + m + n - 1).
From Vincenzo Librandi, Mar 05 2012: (Start)
G.f.: x*(2 + 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
CoefficientList[Series[(2+3*x-2*x^2)/(1-x)^4, {x, 0, 40}], x] (* or *) LinearRecurrence[{4, -6, 4, -1}, {2, 11, 30, 62}, 50] (* Vincenzo Librandi, Mar 05 2012 *)
Table[(n^3+4 n^2-n)/2, {n, 50}] (* Harvey P. Dale, Jul 05 2020 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Jun 29 2009
EXTENSIONS
New name from Vincenzo Librandi, Mar 05 2012
STATUS
approved