Arithmetic progression, Geometric progression and Harmonic progression

5 replies · 2K views · last reply
pairofstrings
Messages
411
Reaction score
7
TL;DR
It looks as if the AP, GP, HP can be used to build any function.
How do I build functions by using Arithmetic Sequence, Geometric Sequence, Harmonic Sequence?
Is it possible to create all the possible function by using these sequences?

Thanks!
 
Sequences are numbers with common difference. f(x) is a sequence and g(x) is a sequence. If there is common difference then there is consistency among numbers. If there is consistency among numbers then I can build an equation.
Example:
The values in the second column of the below table have consistent numbers for given input 'x' for drawing a graph of f(x) or g(x) .
So the equation is:

y = f(x) = x + 2;

xf(x) = y
-20
-11
02
13
24

y = g(x) = 3x + 2

xg(x) = y
-3-7
-2-4
-1-1
02
15
28
311

So, all functions have consistent numbers?
What about this:
Normal distribution probability density function: f(x) = 1/(σ√(2π)) · e^(−½((x−μ)/σ)²)
 
Last edited:
Not all functions are one of these progressions. First of all, these progressions are only defined for integers, so you'll never catch functions defined on other sets, like the real numbers. But it doesn't even work for integers. Simple counterexamples are f(x)=x3 or g(x)=|x| or h(x)=sin(x). The Gaussian distribution you posted is a counterexample, too. Only a very limited set of functions can be made with the three progressions you listed.
 
mfb said:
Only a very limited set of functions can be made with the three progressions you listed.
If there is a pattern of numbers that have consistent numbers in it then any function can be created. No?
 
Last edited: