The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
. By a hole graph we mean a 2-connected planar graph where no two nontriangular faces have a vertex in common. We give necessary and sufficient conditions for a hole graph to be 3-colorable.
It is known that the functions FG(k) and IG(k) evaluating the numbers of nowhere-zero k- and k-flows in a graph G, respectively, are polynomials of k. If X is a totally cyclic orientation of G, then the number of integral flows having values 1,,k1 on the arcs of X can be evaluated by a polynomial IX(k). FG(k) and IG(k) can be expressed as sums of IX(k). In this paper we show that the value IX(k) is...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.