a(n) = F(F(n)) mod F(n), where F = Fibonacci = A000045.

Terms

a(0) =0a(1) =0a(2) =1a(3) =2a(4) =0a(5) =5a(6) =12a(7) =5a(8) =33a(9) =5a(10) =1a(11) =0a(12) =232a(13) =233a(14) =55a(15) =5a(16) =1596a(17) =2563a(18) =1a(19) =5a(20) =987a(21) =10946a(22) =28656a(23) =0a(24) =0a(25) =75025a(26) =189653a(27) =89a(28) =1a(29) =6765