# decreasing/increasing series/sequence of numbers/values

I need help regarding an issue related to slope of a line (derived from a set of values). I would like to write this in Math terms, specifically to show that the values are decreasing/increasing/flat

To be clear, by "Math/formulaic terms", i mean something like... x1>x2>x3, or m = (y2-y1)/(x2-x1)

Let's work on some close-to-actual values: (decreasing in this case) A1 = .5960 A2 = .5958 A3 = .5957 A4 = .5955 A5 = .5951 A6 = .5950 A7 = .5942 A8 = .5941 A9 = .5940 A10 = .5938 A11 = .5930 A12 = .5930 A13 = .5932 A14 = .5927 A15 = .5930 A16 = .5930 A17 = .5930 A18 = .5930 A19 = .5928 A20 = .5924 A21 = .5920 A22 = .5919 A23 = .5916 A24 = .5913 A25 = .5909 A26 = .5904 A27 = .5900

Question: 1. how do you display in formulaic/Math terms that "A1 to A27 is decreasing/generally decreasing"? Are there several ways to write this down as a formula/Math term, perhaps a long and short version? 2. I believe A14 to A18 will look flat when these values are plotted as a line. If this is correct, how do you display in formulaic terms that "A14 to A18 is flat"? 3. If I consider A1 to A16 as one group, and A17 to A27 as another group, how do I write, in Math/formulaic terms, that the "slope is decreasing because Group2 is less than Group 1"? 4. if A1 to A27 were increasing in value, what would your answers be for questions 1 to 3 above?

Could you help? I believe some of you would find this easy. I think my Math skills are above average, so I would like to request that you would explain your replies with as much details as possible/necessary. Thanks!

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