Sequential Spaces

The first paper below initiated the study of sequential spaces in topology. It and its sequel, number 3, contain the fundamental theorems on the subject. The 1991 Mathematics Subject Index, compiled by the American Mathematical Society, contains the designation, 54D55 Sequential Spaces. The 1993 Annual Index of Mathematical Reviews, almost thirty years later, mentions some 10 papers citing 54D55. Number 5 was, in its time the only joint paper by an American and a Russian. Number 6 spawned the study of a class of spaces now called Franklin-Rajagopalan spaces.

1. "Spaces in Which Sequences Suffice," Fundamenta Mathematicae 67 (1965), 107- 116.

2. "On Unique Sequential Limits," Nieuw Arch. Der Wisk. 14 (1965), 12-14.

3. "Spaces of Which Sequences Suffice, II," Fund. Math. 61 (1967), 51-56. 4. "On k-spaces and sequential spaces," a widely cited but unpublished set of class notes from Carnegie Mellon University.

5. "Ordinal Invariants on Topological Spaces," Michigan Math. J. 15 (1968), 313-320 (with A. B. Arhangelskii).

6. "Some Examples in Topology," Trans. Amer. Math. Soc. 155 (1971), 305-3l4 (with M. Rajagopalan).

7. "On subspaces of sequential spaces" (with M. Rajagopalan), Topology and its Applications 35(1990) 1-19.