%I #3 Sep 08 2013 13:31:20
%S 1,1,1,2,4,9,22,56,152,428,1257
%N Eigensequence of A053121.
%F a(n)=Sum_[k, 0<=k<=n-1}A053121(n-1,k)*a(k)for n>0 with a(0)=1 .
%K nonn
%O 0,4
%A _Philippe Deléham_, Jun 16 2007