diff --git a/benchmarks/1d/progression.geo b/benchmarks/1d/progression.geo
index 00031c6bb32162f42d6f3431f7bef061c72afbd2..b7f38af62f0323d0dff0f9bdbb0e2954080b7ee0 100644
--- a/benchmarks/1d/progression.geo
+++ b/benchmarks/1d/progression.geo
@@ -6,7 +6,26 @@ Point(3) = {3,0,0,1};
 Point(4) = {7,0,0,1};
 Point(5) = {15,0,0,1};
 
-Point(6) = {0,0.2,0,1};
-Point(7) = {15,0.2,0,1};
+n = 4; // number of intervals
+r = 2; // progression
+
+// progression using transfinite mesh
+
+Point(6) = {0,0.4,0,1};
+Point(7) = {15,0.4,0,1};
 Line(1) = {6,7};
-Transfinite Line {1} = 5 Using Progression 2;
+Transfinite Line {1} = n+1 Using Progression r;
+
+// progression using extruded mesh
+
+a = (r - 1) / (r^n - 1);
+one[0] = 1;
+layer[0] = 0;
+For i In {1:n}
+  one[i] = 1;
+  layer[i] = layer[i-1] + a * r^(i-1);
+EndFor
+Point(10) = {0,0.8,0,1};
+Extrude {15,0,0} {
+  Point{10}; Layers{one[], layer[]};
+}