Jacobsthal sum

From HandWiki

In mathematics, Jacobsthal sums are finite sums of Legendre symbols related to Gauss sums. They were introduced by Jacobsthal (1907).

Definition

The Jacobsthal sum is given by

[math]\displaystyle{ \phi_n(a)=\sum_{m\bmod p}\left(\dfrac{m(m^n+a)}{p}\right) }[/math]

where p is prime and () is the Legendre symbol.

References

Further reading

  • Storer, Thomas (1967), Cyclotomy and difference sets, Chicago: Markham Publishing Company