A175702 - OEIS

%I #3 Mar 30 2012 18:35:52

%S 1,-2,-1,4,-3,2,-1,-4,9,-2,-5,0,1,6,3,-8,-3,2,7,-4,1,-2,-1,12,1,-10,

%T -5,-8,13,10,-1,-12,1,6,3,0,-7,6,11,-8,-3,-6,-1,-4,-3,2,7,12,21,-14,

%U -5,-16,-7,22,-5,-8,-3,2,19,16,-7,-10,7,-4,-3,-22,-9,-12,13,10,7,12,5,10,-9

%N Convolution square of the Liouville sequence A008836.

%F a(n)= Sum_{k=1..n} lambda(k)*lambda(n+1-k).

%p with(numtheory): T:=array(1..200):for p from 1 to 200 do: T[p] :=(-1)^bigomega(p): od :for n from 1 to 100 do: printf(`%d, `, sum (T[k]*T[n+1-k],k=1..n)):od:

%Y Cf. A002819, A007421

%K sign

%O 1,2

%A _Michel Lagneau_, Aug 10 2010

%E Definition slightly rephrased, keyword:sign added - _R. J. Mathar_, Aug 19 2010