2789

This number is a prime.

T. D. Noe found that 2789 is the smallest prime that does not divide any term of the Lucas 4-step sequence, i.e., Tetranacci numbers with different initial conditions: a(n)=a(n-1)+a(n-2)+a(n-3)+a(n-4), a(0)=4, a(1)=1, a(2)=3, a(4)=7. [Post]