a(n) = |a(n-1) + 2a(n-2) - n|.

Terms

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