A105569 - OEIS

%I #2 Mar 30 2012 18:59:06

%S 1,1,2,0,3,3,2,2,0,1,2,0,0,-1,2,2,2,-3,2,2,4,-1,2,0,2,1,2,-1,2,-2,2,3,

%T 8,0,2,-1,4,0,2,3,4,-1,2,2,6,-4,2,3,6,4,2,-2,2,-2,2,4,4,-1,2,4,6,9,2,

%U -1,0,-3,2,-4,6,0,2,3,12,9,2,-1,-6,-6,2,2,6,4,2,6,8,0,2,1,0,0,2,6,0,-6,2,5,8,0,2,3,4

%N Diagonal sums of A105567, as a number triangle.

%F a(n)=sum{k=0..floor(n/2), -mu(k(n-2k))}

%K easy,sign

%O 0,3

%A _Paul Barry_, Apr 14 2005