Wall-Sun-Sun Prime

Author

Eric W. Weisstein
November 3, 2005

This notebook downloaded from http://mathworld.wolfram.com/notebooks/PrimeNumbers/Wall-Sun-SunPrime.nb.

For more information, see Eric's MathWorld entry http://mathworld.wolfram.com/Wall-Sun-SunPrime.html.

©2005 Wolfram Research, Inc. except for portions noted otherwise

Congruences

Function[p,Mod[Fibonacci[p-JacobiSymbol[p,5]],p^2]]/@Prime[Range[10]]

Position[Function[p,Mod[Fibonacci[p-JacobiSymbol[p,5]],p^2]]/@Prime[Range[10^4]],0]//Timing

Position[Function[p,Mod[Fibonacci[p-JacobiSymbol[p,5]],p^2]]/@Prime[Range[10^5]],0]//Timing

Identity

l=Function[p,Mod[{Expand@LucasL[p-(j=JacobiSymbol[p,5])],2j},p^2]]/@Prime[Range[100]]

And@@(Equal@@@Drop[l,3])

Last/@l