diff --git a/gramps/gui/widgets/fanchart.py b/gramps/gui/widgets/fanchart.py
index 9a18d01d4..002cecc62 100644
--- a/gramps/gui/widgets/fanchart.py
+++ b/gramps/gui/widgets/fanchart.py
@@ -350,7 +350,7 @@ class FanChartBaseWidget(Gtk.DrawingArea):
             self.maincolor = cstart
         elif self.background == BACKGROUND_GRAD_GEN:
             #compute the colors, -1, 0, ..., maxgen
-            divs = [x/(maxgen-1) for x in range(maxgen)]
+            divs = [x/(maxgen-1) for x in range(maxgen)] if maxgen>1 else [0]
             rgb_colors = [colorsys.hsv_to_rgb(
                             (1-x) * self.cstart_hsv[0] + x * self.cend_hsv[0], 
                             (1-x) * self.cstart_hsv[1] + x * self.cend_hsv[1],
diff --git a/gramps/gui/widgets/fanchartdesc.py b/gramps/gui/widgets/fanchartdesc.py
index 3b0024208..9dc9ef167 100644
--- a/gramps/gui/widgets/fanchartdesc.py
+++ b/gramps/gui/widgets/fanchartdesc.py
@@ -158,10 +158,10 @@ class FanChartDescWidget(FanChartBaseWidget):
         self.gen2fam[0] = [] #no families
         self.angle = {}
         self.angle[-2] = []
-        for i in range(1, self.generations-1):
+        for i in range(1, self.generations+1):
             self.gen2fam[i] = []
             self.gen2people[i] = []
-        self.gen2people[self.generations-1] = [] #indication of more children
+        self.gen2people[self.generations] = [] #indication of more children
         self.rotfactor = 1
         self.rotstartangle = 0
         if self.form == FORM_HALFCIRCLE: