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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..45.

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

Cf. A211241, A305332, A305333.

Sequence in context: A262888 A262894 A262890 * A169769 A191688 A051767

Adjacent sequences:  A305328 A305329 A305330 * A305332 A305333 A305334

KEYWORD

nonn

AUTHOR

Felix Fröhlich, May 30 2018

STATUS

approved

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Last modified September 27 16:20 EDT 2020. Contains 337383 sequences. (Running on oeis4.)