%I #16 Mar 11 2014 01:32:11
%S 1,-2,-1,2,-1,4,-2,0,3,0,-1,-2,1,2,6,-8,0,-2,3,0,5,-4,2,-2,1,-2,1,-6,
%T 5,-2,4,-4,5,0,10,-6,-7,-2,2,-4,3,-2,1,-4,-1,4,10,4,4,-14,-1,-4,8,2,2,
%U -12,-3,2,13,10,-11,-10,-2,-6,13,-6,-5,-8,5,2,18,10,-5,-6,-9,0
%N Sum{k=1 to n} mu(k) mu(n+1-k), where mu(k) is the Moebius function.
%H Reinhard Zumkeller, <a href="/A068341/b068341.txt">Table of n, a(n) for n = 1..10000</a>
%t a[n_] := Sum[ MoebiusMu[k]*MoebiusMu[n + 1 - k], {k, 1, n}]; Table[ a[n], {n, 1, 76}] (* _Jean-François Alcover_, Oct 10 2011 *)
%o (Haskell)
%o a068341 n = a068341_list !! (n-1)
%o a068341_list = f 1 [] where
%o f x ms = (sum $ zipWith (*) ms' $ reverse ms') : f (x + 1) ms' where
%o ms' = (a008683 x) : ms
%o -- _Reinhard Zumkeller_, Aug 03 2012
%K sign
%O 1,2
%A _Leroy Quet_, Feb 27 2002
|