[R] Legendre symbols

[Robin Hankin]

Hi

before I reinvent the wheel, has anyone coded up the Legendre symbol  
(a/p)?

[
If p is an odd prime number and a is an integer, then the Legendre  
symbol
(a/p)   is:

     * 0 if p divides a;
     * 1 if a is a square modulo p — that is to say there exists an  
integer k such that k^2 ≡ a (mod p)
     * −1 if not

[courtesy Wikipedia]

]

I might also need Jacobi's generalization of this.




--
Robin Hankin
Uncertainty Analyst
National Oceanography Centre, Southampton
European Way, Southampton SO14 3ZH, UK
  tel  023-8059-7743