a(n) = Sum_{k=0..n} (-k)^k.

Terms

a(0) =1a(1) =0a(2) =4a(3) =-23a(4) =233a(5) =-2892a(6) =43764a(7) =-779779a(8) =15997437a(9) =-371423052a(10) =9628576948a(11) =-275683093663