a(n) = Fibonacci(n) - n.

Terms

a(0) =0a(1) =0a(2) =-1a(3) =-1a(4) =-1a(5) =0a(6) =2a(7) =6a(8) =13a(9) =25a(10) =45a(11) =78a(12) =132a(13) =220a(14) =363a(15) =595a(16) =971a(17) =1580a(18) =2566a(19) =4162a(20) =6745a(21) =10925a(22) =17689a(23) =28634a(24) =46344a(25) =75000a(26) =121367a(27) =196391a(28) =317783a(29) =514200