a(1)=5, a(n) = a(n-1)*(a(n-1)-1)*(a(n-1)-2)/6.A251702a(1)=5, a(n) = a(n-1)*(a(n-1)-1)*(a(n-1)-2)/6.Terms a(0) =5a(1) =10a(2) =120a(3) =280840External referencesoeis: A251702