A054769 Number of integer n-tuples {x(1},x(2),...,x(n)} with the following properties: (1) x(1)=1 and, for k>1, if d=x(k)-x(k-1), then (2) d is relatively prime to x(k-1) and (3) d=x(i) for some i in {1,2,...,(k-1)}.

1, 1, 1, 2, 5, 17, 67, 324, 1777, 11054, 76793, 591905