OFFSET
1,1
COMMENTS
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..10000
Index entries for linear recurrences with constant coefficients, signature (2,-1).
FORMULA
G.f.: x*(228 - 12*x)/(x-1)^2. - Vincenzo Librandi, Jan 30 2012 [corrected by Georg Fischer, May 12 2019]
a(n) = 2*a(n-1) - a(n-2). - Vincenzo Librandi, Jan 30 2012
a(n) = 12*A161705(n). - Michel Marcus, Aug 19 2018
MATHEMATICA
LinearRecurrence[{2, -1}, {228, 444}, 50] (* Vincenzo Librandi, Jan 30 2012 *)
PROG
(PARI) a(n)=216*n+12 \\ Charles R Greathouse IV, Dec 27 2011
(Magma) I:=[228, 444]; [n le 2 select I[n] else 2*Self(n-1)-Self(n-2): n in [1..50]]; // Vincenzo Librandi, Jan 30 2012
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Jan 11 2009
STATUS
approved