Signed variant of A077012.

Terms

a(0) =1a(1) =-1a(2) =2a(3) =2a(4) =-3a(5) =6a(6) =-6a(7) =8a(8) =-12a(9) =24a(10) =24a(11) =-30a(12) =40a(13) =-60a(14) =120a(15) =-120a(16) =144a(17) =-180a(18) =240a(19) =-360a(20) =720a(21) =720a(22) =-840a(23) =1008a(24) =-1260a(25) =1680a(26) =-2520a(27) =5040a(28) =-5040a(29) =5760