Abstract

This paper is the third part of the publication ``Selected chapters of algebra'', the first two being published in the previous issues of the Teaching of Mathematics, Vol\. I (1998), 1--22, and Vol\. II, 1 (1999), 1--30.

Keywords: Set, subset, one-to-one correspondence, combinatorics.

Pages:  65$-$80     

Volume  II ,  Issue  2 ,  1999