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

Terms

a(0) =0a(1) =-24a(2) =240a(3) =-504a(4) =480a(5) =-264a(6) =94a(7) =-24a(8) =4a(9) =-1a(10) =0a(11) =-1a(12) =0a(13) =-1a(14) =0a(15) =-1a(16) =0a(17) =-1a(18) =0a(19) =-1a(20) =0a(21) =-1a(22) =0a(23) =-1a(24) =0a(25) =-1a(26) =0a(27) =-1a(28) =0a(29) =-1