OFFSET
0,3
LINKS
Bruno Berselli, Table of n, a(n) for n = 0..300
Index entries for linear recurrences with constant coefficients, signature (8, 27).
FORMULA
G.f.: x/(1-8*x-27*x^2).
a(n) = ((4+sqrt(43))^n - (4-sqrt(43))^n)/(2*sqrt(43)).
MATHEMATICA
a = {0, 1}; Do[AppendTo[a, 8 a[[-1]] + 27 a[[-2]]], {18}]; a (* Bruno Berselli, Dec 26 2012 *)
CoefficientList[Series[x / (1 - 8 x - 27 x^2), {x, 0, 25}], x] (* Vincenzo Librandi, Aug 19 2013 *)
PROG
(Maxima) a[0]:0$ a[1]:1$ a[n]:=8*a[n-1]+27*a[n-2]$ makelist(a[n], n, 0, 17);
(Magma) [n le 2 select n-1 else 8*Self(n-1)+27*Self(n-2): n in [1..17]];
(PARI) x='x+O('x^30); concat([0], Vec(x/(1-8*x-27*x^2))) \\ G. C. Greubel, Dec 30 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Bruno Berselli, May 24 2011
STATUS
approved