accident?

[Ralf Stephan]

Emeric Deutsch: 
> The only answer is 
> 	1,1,1,2,5,13,33,80,184,402,840

%N A001659 Expansion of bracket function.

May I ask Neil to add:
%C A001659 a(n) seems to be the negative of pairwise sums of A038200.
(thanks) where

%V A038200 1,0,-1,3,-8,21,-54,134,-318,720,-1560,3259,-6641,13391,...
%N A038200 Row sums of triangle K(m, n), inverse to triangle T(m,n) in A020921.
where
%N A020921 Triangle T(m,n) = number of solutions to 1 <= a(1)<a(2)<...<a(m) <= n, where GCD( a(1), a(2), ....a(m), n)=1.

Does the 'bracket function' have to do with this?
Is there a short definition?


ralf