# Browse Classroom Capsules and Notes

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Displaying 81 - 90 of 133

A simple proof for Last Fermat Theorem when n=4 in Gaussian Integers

Goldbach's conjecture on the expression of odd numbers and some examples

The existence of an odd perfect number is related to the abundancy index.

All but finite numbers of integers can be written as a sum of $N$ squares, where $N$ is between 5 and 156.

The author gives a new formulation of the conjecture.

If two elements in a ring are multiples of each other, are they necessarily unit multiples? In general, the answer is no; it is yes for the integers mod $n$.