OFFSET
0,3
COMMENTS
LINKS
Harry J. Smith, Table of n, a(n) for n = 0..1000
T. P. Martin, Shells of atoms, Phys. Reports, 273 (1996), 199-241, eq. (11).
Index entries for linear recurrences with constant coefficients, signature (4, -6, 4, -1).
FORMULA
G.f.: x*(1+12*x+x^2)/(1-x)^4. - Colin Barker, Jan 10 2012
E.g.f.: (x/3)*(3 + 21*x + 7*x^2)*exp(x). - G. C. Greubel, Sep 01 2017
MAPLE
MATHEMATICA
lst={}; Do[AppendTo[lst, n*(7*n^2-4)/3], {n, 1, 6!}]; lst (* Vladimir Joseph Stephan Orlovsky, Sep 02 2008 *)
CoefficientList[Series[x*(1+12*x+x^2)/(1-x)^4, {x, 0, 50}], x] (* G. C. Greubel, Sep 01 2017 *)
PROG
(PARI) { for (n=0, 1000, write("b063521.txt", n, " ", n*(7*n^2 - 4)/3) ) } \\ Harry J. Smith, Aug 25 2009
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Aug 02 2001
STATUS
approved