OFFSET
0,1
COMMENTS
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (6, -8).
FORMULA
a(n) = 2*4^(n+5)-2017*2^(n-1) for n > 2.
G.f.: (191+441*x+6167*x^2+50734*x^3-116584*x^4) / ((1-2*x)*(1-4*x)).
G.f. for the sequence starting at a(3): 4*x^3*(30751-57468*x) / ((1-2*x)*(1-4*x)).
MATHEMATICA
Join[{191, 1587, 14161}, Transpose[NestList[{Last[#], 6Last[#]-8First[#]}&, {123004, 508152}, 20]][[1]]] (* Harvey P. Dale, Mar 06 2011 *)
CoefficientList[Series[(191 + 441 x + 6167 x^2 + 50734 x^3 - 116584 x^4)/((1 - 2 x) (1 - 4 x)), {x, 0, 40}], x] (* Vincenzo Librandi, Sep 24 2013 *)
LinearRecurrence[{6, -8}, {191, 1587, 14161, 123004, 508152}, 20] (* Harvey P. Dale, Oct 16 2019 *)
PROG
(PARI) {m=19; v=concat([191, 1587, 14161, 123004, 508152], vector(m-5)); for(n=6 , m, v[n]=6*v[n-1]-8*v[n-2]); v}
(Magma) [191, 1587, 14161] cat [2*4^(n+5)-2017*2^(n-1): n in [3..25]]; // Vincenzo Librandi, Sep 24 2013
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Klaus Brockhaus, May 12 2010
STATUS
approved