login
A171874
a(n) = a(n-1) + a(n-2)*a(n-3) + a(n-4)^a(n-5).
1
0, 0, 0, 1, 1, 2, 4, 7, 16, 46, 174, 3311, 268446771, 401906756202069927727330981
OFFSET
0,6
COMMENTS
First 5 terms are {0,0,0,1,1}; thereafter apply the recurrence. Note that 0^0=1.
LINKS
PROG
(Magma) I:=[0, 0, 0, 1, 1]; [n le 5 select I[n] else Self(n-1)+Self(n-2)*Self(n-3)+(Self(n-4))^Self(n-5): n in [1..14]]; // Vincenzo Librandi, Dec 18 2012
(Haskell)
import Data.List (zipWith5)
a171874 n = a171874_list !! n
a171874_list = [0, 0, 0, 1, 1] ++ zipWith5 (\z y x w v -> z + x*y + w^v)
(drop 4 a171874_list) (drop 3 a171874_list)
(drop 2 a171874_list) (tail a171874_list) a171874_list
-- Reinhard Zumkeller, Aug 14 2013
CROSSREFS
Sequence in context: A137568 A010355 A171880 * A113878 A293793 A301745
KEYWORD
nonn
AUTHOR
Robert Munafo, Jan 21 2010
STATUS
approved