The phrase "an interesting quantity" is correct and usable in written English.
You can use it when discussing a specific measurement or value that captures attention or curiosity in a scientific, mathematical, or analytical context.
Example: "In our research, we discovered an interesting quantity that could potentially change our understanding of the phenomenon."
Alternatives: "a noteworthy figure" or "a fascinating value".
From a biological perspective the most interesting quantity of the interaction kernel is its range, i.e. the distance on which cells communicate and influence each other.
The numerical integration of stochastic trajectories to estimate the time to pass a threshold is an interesting physical quantity, for instance in Josephson junctions and atomic force microscopy, where the full trajectory is not accessible.
This is especially true of the timing of the expansion out of Africa, which is usually the most interesting quantity.
In the A-model of topological string theory, physically interesting quantities are expressed in terms of infinitely many numbers called Gromov Witten invariants, which are extremely difficult to compute.
Choose some quantities to record like the time you wake up or go to sleep, how much time you spend with digital media, how many text messages or e-mails you send and receive, how you spend time on Facebook or other interesting quantities.
The most interesting quantities calculated by Gimlet are power spectra of the Lyman-α flux and matter density.
Moreover, we show how we can compute in Θ(n) time several interesting quantities in, that can be possibly used as building blocks for computing efficiently the skewness of other phylogenetic measures.
In one group of problems an interesting trick is used: "A quantity (aha) and its 7th together make 19 what is it?" (Rhind papyrus, problem 24).
"While quantity is certainly an interesting piece of data, that information did not help software developers drive traffic to Amazon.com," said Drew Herdener, a spokesman for Amazon.
These individual accusations of Hitler-dom are pretty boring, but their sheer quantity points to an interesting question: Who in world history is the most like Hitler?
