eluer
it is not about maths.
The mean is usually the arithmetic mean - there are other means in maths. For a set of numbers, the arithmetic mean is the sum of the numbers divided by the number of numbers.
math and arithmetic
ramanujan
everywhere!!
There is no simple answer because there is no simple rule for primes: it is certainly NOT an arithmetic progression.
Erdos' Conjecture on Arithmetic Progressions (Wikipedia.org)
Harmonic progressions is formed by taking the reciprocals of an arithmetic progression. So if you start with some number a, and add a common difference d each time, the arithmetic progression would be a, a+d, a+2d, a+3d etc. The harmonic progression comes from taking the reciprocals of these terms. So we have a, a/(1+d), a/(1+2d), a/( 1+3d)... Here is a harmonic progression: 1/6, 1/4, 1/3, ....
eluer
Maths and Arithmetic
it is not about maths.
ramanujan
The mean is usually the arithmetic mean - there are other means in maths. For a set of numbers, the arithmetic mean is the sum of the numbers divided by the number of numbers.
math and arithmetic
ramanujan
Arithmetic is actually a small branch of maths (the basic addition, subtraction and multiplication stuff), rather than all maths in general. The reason it's called arithmetic is the same reason algebra is called "algebra" - both words descend from ancient Arabic. (Maths existed before it was named by the ancient Arab's, however it was not called arithmetic/algebra). "Arithmetic" has been around (as a word) since the 3rd AD.