Home > Iowa Academy of Science > Proceedings of the Iowa Academy of Science > Volume 48 (1941) > Annual Issue

#### Article Title

#### Document Type

Research

#### Abstract

Given a topological space in which the operation of closure of a set, here denoted by 'e', has the properties: e (A+B) = eA+eB; A is a subset of eA, eO = 0, e^{2}A = eA (where A is any subset of the space and 0 is the null set), we may define the interior 'i' of a set A by the formula iA = cecA (where cA denotes the complement of A in the space) and write a formula entirely equivalent to one due to C. Kuratowski (Fundamenta Mathematicae, III (1922), p. 183) in the following way: (1) (ei)^{2}A = eiA.

#### Publication Date

1941

#### Journal Title

Proceedings of the Iowa Academy of Science

#### Volume

48

#### Issue

1

#### First Page

299

#### Last Page

300

#### Copyright

©1941 Iowa Academy of Science, Inc.

#### Language

en

#### File Format

application/pdf

#### Recommended Citation

Chittenden, E. W.
(1941)
"A New Proof of a Formula of Kuratowski,"
*Proceedings of the Iowa Academy of Science, 48(1),* 299-300.

Available at:
https://scholarworks.uni.edu/pias/vol48/iss1/73