Number Theory

Additive functions and special sets of integers.- Some new problems and results in number theory.- Some recent results on positive values of non-homogeneous indefinite quadratic forms.- On a number of theoretical problems involved in the study of the physics of spin-systems.- Order-free integers (mod m).- Perfect totient numbers.- A brief summary of some results in the analytic theory of numbers-II.- Addendum to my paper a brief summary of some results in the analytic theory of numbers.- Some ?-results for Ramanujan's ?-function.- On certain expoential and character sums.- Partitions with congruence conditions and color restrictions.- Problem session (Chaired by Prof. P. Erdös) two problems proposed by K. Ramachandra.