diff --git a/cmd/convergents.go b/cmd/convergents.go
index 3daa8e8..3d665e9 100644
--- a/cmd/convergents.go
+++ b/cmd/convergents.go
@@ -24,6 +24,14 @@ import (
 	"github.com/spf13/cobra"
 )
 
+func seq(x, xprev, a *big.Int) {
+	tmp := new(big.Int)
+	tmp.Mul(a, x)
+	tmp.Add(tmp, xprev)
+	xprev.Set(x)
+	x.Set(tmp)
+}
+
 func convergents(cmd *cobra.Command, args []string) {
 	hprev := big.NewInt(0)
 	kprev := big.NewInt(1)
@@ -44,32 +52,14 @@ func convergents(cmd *cobra.Command, args []string) {
 		}
 	}
 
-	tmp := new(big.Int)
-	tmp.Mul(a0, h)
-	tmp.Add(tmp, hprev)
-	hprev.Set(h)
-	h.Set(tmp)
-
-	tmp.Mul(a0, k)
-	tmp.Add(tmp, kprev)
-	kprev.Set(k)
-	k.Set(tmp)
-
+	seq(h, hprev, a0)
+	seq(k, kprev, a0)
 	fmt.Println(h, k)
 
 	for i := 0; true; i = (i + 1) % len(denoms) {
 		a := &denoms[i]
-
-		tmp.Mul(a, h)
-		tmp.Add(tmp, hprev)
-		hprev.Set(h)
-		h.Set(tmp)
-
-		tmp.Mul(a, k)
-		tmp.Add(tmp, kprev)
-		kprev.Set(k)
-		k.Set(tmp)
-
+		seq(h, hprev, a)
+		seq(k, kprev, a)
 		fmt.Println(h, k)
 	}
 }