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A305331
Multiplicative order of 5 (mod p^2), where p = prime(n), or 0 if 5 and p are not coprime.
2
1, 6, 0, 42, 55, 52, 272, 171, 506, 406, 93, 1332, 820, 1806, 2162, 2756, 1711, 1830, 1474, 355, 5256, 3081, 6806, 3916, 9312, 2525, 10506, 11342, 2943, 12656, 5334, 8515, 18632, 9591, 5513, 11325, 24492, 8802, 27722, 29756, 15931, 2715, 3629, 37056, 38612
OFFSET
1,2
MATHEMATICA
Table[If[p==5, 0, MultiplicativeOrder[5, p^2]], {p, Prime@ Range@ 45}] (* Giovanni Resta, May 31 2018 *)
PROG
(PARI) a(n) = my(p=prime(n)); if(p==5, return(0), return(znorder(Mod(5, p^2))))
CROSSREFS
KEYWORD
nonn
AUTHOR
Felix Fröhlich, May 30 2018
STATUS
approved