A nonsense sequence.

Terms

a(0) =1a(1) =-2a(2) =3a(3) =-1a(4) =1a(5) =-3a(6) =6a(7) =-7a(8) =5a(9) =-1a(10) =1a(11) =-4a(12) =10a(13) =-16a(14) =19a(15) =-15a(16) =7a(17) =-1a(18) =1a(19) =-5a(20) =15a(21) =-30a(22) =45a(23) =-51a(24) =44a(25) =-26a(26) =9a(27) =-1a(28) =1a(29) =-6