If n=r*2^s, r odd, then a(n)=t*r, where t is smallest (in magnitude) number such that 1=t*r+u*2^s.

Terms

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