2,2

It appears that a(p)= p-1 (for prime p) and a(2p) = p-1 (for odd prime p), but this is only speculation. I (or someone else) need to calculate more values of a(n) to settle this conjecture.

E.g.: m mod 4 = {0,1,2,3,0,1,2,3,...}; m^2 mod 4 = {0,1,0,1,...}; m^3 mod 4= {0,1,0,3,0,1,0,3,...}; but m^4 mod 4 = {0,1,0,1} = m^2 mod 4; so for higher powers of m these sequences cycle, and are not unique, thus for mod 4 we have {0,1,2,3}, {0,1}, and {0,1,0,3} as unique and a(4) = 3

Sequence in context: A120636 A117744 A091732 this_sequence A061020 A047994 A117009

Adjacent sequences: A109743 A109744 A109745 this_sequence A109747 A109748 A109749

nonn

Bruce Corrigan (scentman(AT)myfamily.com), Aug 10 2005