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]
The only prime of form p=q*R(q)+q+R(q), where q is a double-digit prime and R(q) its reversal, (q=29). [Loungrides]
(There are 4 curios for this number that have not yet been approved by an editor.)
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