The phrase "a coincidence at" is correct and usable in written English.
It can be used when referring to an unexpected occurrence or event that happens at a specific time or place.
Example: "It was quite a coincidence at the party when I ran into my old friend from high school."
Alternatives: "an occurrence at" or "a chance event at".
And, of course, it's not a coincidence at all.
This close match is a coincidence at least in part, of course.
(Odds are on a coincidence at the moment, though I have to wonder if somebody didn't meddle with it).
You can't have a coincidence at the beginning... well, I mean, perhaps you can have a coincidence in the first chapter.
I decided to make a happy coincidence not a coincidence at all! Can you tell us more about the three children of Loki and how you have constructed their personalities?
When, as a girl, I inquired about this coincidence, my mother told me it was not a coincidence at all but a choice: some women from big families decided they did not want children, did not want that life, which, she said, was very difficult.
It probably isn't a coincidence that, at the age of nearly 79, Eric Rohmer has at last begun to feature older people.
"About two weeks after I arrived in town," Ms. Zicklin said, "we met again -- a coincidence -- at 12th and Porter, which is a Nashville bar and restaurant.
So I don't think it's a coincidence that, at the United Nations, Mr. Obama vigorously defended free speech rights.
Maybe it's not a coincidence that, at a time when so many public figures seem to be having trouble staying within the lines, coloring books have made a comeback.
I don't think it's a coincidence that at the time, the empire was able to grow to its greatest extent, while the city of Rome also had a population of as many as 1.5 million".
