a(n) = ceiling((-4n)/Bernoulli(2n)).

Terms

a(0) =0a(1) =-24a(2) =240a(3) =-504a(4) =480a(5) =-264a(6) =95a(7) =-24a(8) =5a(9) =0a(10) =1a(11) =0a(12) =1a(13) =0a(14) =1a(15) =0a(16) =1a(17) =0a(18) =1a(19) =0a(20) =1a(21) =0a(22) =1a(23) =0a(24) =1a(25) =0a(26) =1a(27) =0a(28) =1a(29) =0