OFFSET
0,3
COMMENTS
First differences give {0, 8, 40, 232, 1320, 7528, 42920, ...} = 8*A015537(n) = 8 * {0, 1, 5, 29, 165, 941, 5365, ...}. - Alexander Adamchuk, Nov 03 2006
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 0..1000
Lucyna Trojnar-Spelina, Iwona Włoch, On Generalized Pell and Pell-Lucas Numbers, Iranian Journal of Science and Technology, Transactions A: Science (2019), 1-7.
Index entries for linear recurrences with constant coefficients, signature (5, 4).
FORMULA
a(n) = Sum_{k=0..n} 4^(n-k)*A122542(n,k).
G.f.: (1-4*x)/(1-5*x-4*x^2).
a(n) = 1 + 8*Sum_{k=0..n} A015537(k). - Alexander Adamchuk, Nov 03 2006
MATHEMATICA
LinearRecurrence[{5, 4}, {1, 1}, 30] (* Harvey P. Dale, Jul 25 2011 *)
PROG
(Haskell)
a123270 n = a123270_list !! n
a123270_list = 1 : 1 : zipWith (-) (map (* 5) $
zipWith (+) (tail a123270_list) a123270_list) a123270_list
-- Reinhard Zumkeller, Aug 16 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Philippe Deléham, Oct 09 2006
STATUS
approved