OFFSET
0,1
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (3,-3,1).
FORMULA
a(0)=81, a(1)=400, a(2)=961, a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3). - Harvey P. Dale, Oct 30 2011
From G. C. Greubel, Oct 28 2019: (Start)
G.f.: (81 + 157*x +4*x^2)/(1-x)^3.
E.g.f.: (81 + 319*x + 121*x^2)*exp(x). (End)
MAPLE
seq((11*n+9)^2, n=0..30); # G. C. Greubel, Oct 28 2019
MATHEMATICA
(11Range[0, 30]+9)^2 (* or *) LinearRecurrence[{3, -3, 1}, {81, 400, 961}, 30] (* Harvey P. Dale, Oct 30 2011 *)
PROG
(PARI) a(n)=(11*n+9)^2 \\ Charles R Greathouse IV, Jun 17 2017
(Magma) [(11*n+9)^2: n in [0..30]]; // G. C. Greubel, Oct 28 2019
(Sage) [(11*n+9)^2 for n in (0..30)] # G. C. Greubel, Oct 28 2019
(GAP) List([0..30], n-> (11*n+9)^2 ); # G. C. Greubel, Oct 28 2019
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved