If you are looking for information about the "feature" film itself:
The specific phrase is a combination of technical search operators and user intent:
While exploring digital archaeology is fun, if you find the search process too technical or risky, here are legitimate ways to watch the film (as of the current year): index of triangle 2009 new
Have you seen "Triangle"? The film's greatest trick is that, like its protagonist, you may find yourself watching it again—and again—looking for clues you missed the first time. Perhaps that's the point.
The pile of identical lockets dropped down the ship's grate and the dozens of dead Sally clones on the upper deck show that the physical world does not reset; only Jess's timeline does. If you are looking for information about the
What follows is a relentless nightmare. One by one, the friends are hunted and killed by an assailant wearing a burlap sack mask, an intentional homage to "Friday the 13th Part 2". The survivor is always Jess, who soon discovers a horrifying truth: she is both the victim and the perpetrator. The "Triangle" is not merely a location but an eternal cycle of punishment, where Jess is condemned to repeat the same sequence of events for eternity.
Has witnessed the deaths, tries to alter the timeline to save her friends, but accidentally facilitates the loop's continuation. The pile of identical lockets dropped down the
The phrase could relate to the mathematical concept of an "index of a triangle," as seen in geometry research papers discussing triangle graphs, point containment algorithms, or indexing of points within triangular grids. Search result 0 from zbMath.org discusses "The Wiener, Szeged and Pi index of the triangle graph," a purely mathematical concept.