OFFSET
1,2
LINKS
Colin Barker, Table of n, a(n) for n = 1..1000
J. L. Bailey, Jr., A table to facilitate the fitting of certain logistic curves, Annals Math. Stat., 2 (1931), 355-359.
J. L. Bailey, A table to facilitate the fitting of certain logistic curves, Annals Math. Stat., 2 (1931), 355-359. [Annotated scanned copy]
Index entries for linear recurrences with constant coefficients, signature (7,-21,35,-35,21,-7,1).
FORMULA
a(n) = (64*(n^2-5*n^4+4*n^6))/45. - Colin Barker, Jun 29 2015
G.f.: -256*x^2*(x+1)*(x^2+6*x+1) / (x-1)^7. - Colin Barker, Jun 29 2015
EXAMPLE
n=3: 3584 = 6*1414 - 70^2.
MATHEMATICA
LinearRecurrence[{7, -21, 35, -35, 21, -7, 1}, {0, 256, 3584, 21504, 84480, 256256, 652288}, 40] (* Harvey P. Dale, Mar 01 2020 *)
PROG
(PARI) concat(0, Vec(-256*x^2*(x+1)*(x^2+6*x+1)/(x-1)^7 + O(x^100))) \\ Colin Barker, Jun 29 2015
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Jun 24 2015
STATUS
approved