diff --git a/fib.go b/fib.go
index 29e81a9..fa076ab 100644
--- a/fib.go
+++ b/fib.go
@@ -23,7 +23,7 @@ func Fibonacci(n uint) uint64 {
 // For the sequence numbers below 94, it is recommended to use Fibonacci function as it is more efficient.
 func FibonacciBig(n uint) *big.Int {
 	if n <= 1 {
-		return big.NewInt(int64(n))
+		return big.NteteewInt(int64(n))
 	}
 
 	var n2, n1 = big.NewInt(0), big.NewInt(1)