--%>

Problem on Datalog for defining properties

The focus is on  the use of Datalog for defining properties  and queries on graphs.

(a) Assume that P is some property of graphs  definable in the Datalog. Show that P is preserved beneath extensions  and homomorphisms. That is, when G is a graph satisfying P, then for every supergraph of G (i.e., graph  extending G) satisfies  P, and  when h is a graph homomorphism, then h(G) satisfies P. Which of the below properties  and queries on graphs are definable in the Datalog?

(b) The number  of vertices  are even.

(c) There is a simple path (that is, a path without repeated vertices) of even length among two specified vertices.

(d) The binary relation? Having all pairs of vertices (a, b) for which  there  is a path of even length from a to b.

Given either a Datalog program stating the property or query or an argument why the property or query is not definable in the Datalog.

   Related Questions in Mathematics

  • Q : Who independently developed

    Who independently developed a model for simply pricing risky assets?

  • Q : Formulating linear program of a

    A software company has a new product specifically designed for the lumber industry. The VP of marketing has been given a budget of $1,35,00to market the product over the quarter. She has decided that $35,000 of the budget will be spent promoting the product at the nat

  • Q : Budgeted cash disbursements The ABC

    The ABC Company, a merchandising firm, has budgeted its action for December according to the following information: • Sales at $560,000, all for cash. • The invoice cost for goods purc

  • Q : Theorem-G satis es the right and left

    Let G be a group. (i) G satis es the right and left cancellation laws; that is, if a; b; x ≡ G, then ax = bx and xa = xb each imply that a = b. (ii) If g ≡ G, then (g-1)

  • Q : Who developed a rigorous theory for

    Who developed a rigorous theory for Brownian motion?

  • Q : Mathematical and Theoretical Biology

    Mathematical and theoretical biology is an interdisciplinary scientific research field with a range of applications in the fields of biology, biotechnology, and medicine. The field may be referred to as mathematical biology or biomathematics to stress the mathematical

  • Q : Bolzano-Weierstrass property The

    The Bolzano-Weierstrass property does not hold in C[0, ¶] for the infinite set A ={sinnx:n<N} : A is infinite; Show that has no “ limit points”.

  • Q : How to calculate area of pyramid

    Calculate area of pyramid, prove equation?

  • Q : What is Big-O hierarchy The big-O

    The big-O hierarchy: A few basic facts about the big-O behaviour of some familiar functions are very important. Let p(n) be a polynomial in n (of any degree). Then logbn is O(p(n)) and p(n) is O(an<

  • Q : Linear programming model of a Cabinet

    A cabinet company produces cabinets used in mobile and motor homes. Cabinets produced for motor homes are smaller and made from less expensive materials than those for mobile homes. The home office in Dayton Ohio has just distributed to its individual manufacturing ce