%0 Journal Article %A Hirschhorn, Michael D. %T On recurrences of Fahr and Ringel arising in graph theory %J Journal of integer sequences %D 2009 %V 12 %N 6 %I mathdoc %U http://geodesic.mathdoc.fr/item/JIS_2009__12_6_a3/ %G en %F JIS_2009__12_6_a3