|
%I #9 Jul 13 2013 12:02:42
%S 1,4,3,2,0,0,0,0,0,5,1,1,1,1,1,6,2,2,0,0,0,0,0,5,1,1,1,1,1,6,2,2,0,0,
%T 0,0,0,5,1,1,1,1,1,6,2,2,0,0,0,0,0,5,1,1,1,1,1,6,2,2,0,0,0,0,0,5,1,1,
%U 1,1,1,6,2,2,0,0,0,0,0,5,1,1,1,1,1,6,2,2,0,0,0,0,0,5,1,1,1,1,1,6,2,2,0,0,0
%N Start with a(0)=1, a(1)=4, a(2)=3, a(3)=2; for n>=3, a(n+1) = mex_i (a(i)+a(n-i)), where mex means smallest nonnegative missing number.
%D R. K. Guy, Unsolved Problems in Number Theory, E27.
%H Reinhard Zumkeller, <a href="/A067017/b067017.txt">Table of n, a(n) for n = 0..10000</a>
%o (Haskell)
%o import Data.List ((\\))
%o a067017 n = a067017_list !! n
%o a067017_list = [1,4,3,2] ++ f [2,3,4,1] where
%o f xs = mexi : f (mexi : xs) where
%o mexi = head $ [0..] \\ zipWith (+) xs (reverse xs)
%o -- _Reinhard Zumkeller_, May 05 2012
%Y Cf. A067016, A067018.
%K nonn,easy
%O 0,2
%A _N. J. A. Sloane_, Feb 17 2002
%E More terms from _John W. Layman_, Feb 20 2002
|
