Abstract :
A G-loop is a loop which is isomorphic to all its loop isotopes. We apply some theorems about permutation groups to get information about G-loops. In particular, we study G-loops of order pq, where p < q are primes and p (q − 1). In the case p = 3, the only G-loop of order 3q is the group of order 3q. The notion “G-loop” splits naturally into “left G-loop” plus “right G-loop.” There exist non-group right G-loops and left G-loops of order n iff n is composite and n > 5.