a(0)=a(1)=1. For n >= 2, if a(n-1) is coprime to n, then a(n) = a(n-1) + a(n-2). Otherwise, a(n)=1.

Terms

a(0) =1a(1) =1a(2) =2a(3) =3a(4) =5a(5) =1a(6) =6a(7) =7a(8) =13a(9) =20a(10) =1a(11) =21a(12) =1a(13) =22a(14) =1a(15) =23a(16) =24a(17) =47a(18) =71a(19) =118a(20) =1a(21) =119a(22) =120a(23) =239a(24) =359a(25) =598a(26) =1a(27) =599a(28) =600a(29) =1199