OFFSET
1,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
Index entries for linear recurrences with constant coefficients, signature (8,0,0,1,-8).
FORMULA
G.f.: ( x*(1+2*x+3*x^3) ) / ( (x-1)*(8*x-1)*(1+x)*(x^2+1) ). - R. J. Mathar, Oct 11 2015
MATHEMATICA
CoefficientList[Series[(1 + 2*x + 3*x^3)/((x - 1)*(8*x - 1)*(1 + x)*(x^2 + 1)), {x, 0, 20}], x] (* Wesley Ivan Hurt, Feb 02 2017 *)
LinearRecurrence[{8, 0, 0, 1, -8}, {1, 10, 80, 643, 5145}, 20] (* Vincenzo Librandi, Feb 03 2017 *)
PROG
(Magma) I:=[1, 10, 80, 643, 5145]; [n le 5 select I[n] else 8*Self(n-1)+Self(n-4)-8*Self(n-5): n in [1..20]]; // Vincenzo Librandi, Feb 03 2017
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
STATUS
approved