change wording

cmd/discreteLog.go

@@ -45,7 +45,7 @@ func ceilSqrt(x *big.Int) *big.Int {
 func babyStepGiantStep(n, b, x, order *big.Int) (*big.Int, error) {
 	z := new(big.Int).GCD(nil, nil, b, n)
 	if z.Cmp(big.NewInt(1)) != 0 {
-		return nil, fmt.Errorf("base %v is not invertible modulo %v", b, n)
+		return nil, fmt.Errorf("base %v and modulus %v are not coprime", b, n)
 	}
 
 	var m *big.Int