OFFSET
5,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 5..1000
Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1).
FORMULA
a(n) = n(2n^2 - 9n + 49)/6 (n >= 5). - Emeric Deutsch, Nov 29 2006
G.f.: x^5*(45 - 113*x + 100*x^2 - 30*x^3)/(1 - x)^4. - Colin Barker, Sep 17 2012
MAPLE
a:=n->n*(2*n^2-9*n+49)/6: seq(a(n), n=5..45); # Emeric Deutsch, Nov 29 2006
MATHEMATICA
Table[Range[n].RotateLeft[Range[n], 4], {n, 5, 51}] (* T. D. Noe, Nov 07 2006 *)
CoefficientList[Series[(45 - 113 x + 100 x^2 - 30 x^3)/(1 - x)^4, {x, 0, 60}], x] (* Vincenzo Librandi, Oct 17 2013 *)
PROG
(Magma) [n*(2*n^2-9*n+49)/6: n in [5..60]]; // Vincenzo Librandi, Oct 17 2013
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
EXTENSIONS
Corrected by T. D. Noe, Nov 07 2006
STATUS
approved