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%I #7 May 31 2018 03:53:11
%S 1,6,0,42,55,52,272,171,506,406,93,1332,820,1806,2162,2756,1711,1830,
%T 1474,355,5256,3081,6806,3916,9312,2525,10506,11342,2943,12656,5334,
%U 8515,18632,9591,5513,11325,24492,8802,27722,29756,15931,2715,3629,37056,38612
%N Multiplicative order of 5 (mod p^2), where p = prime(n), or 0 if 5 and p are not coprime.
%t Table[If[p==5, 0, MultiplicativeOrder[5, p^2]], {p, Prime@ Range@ 45}] (* _Giovanni Resta_, May 31 2018 *)
%o (PARI) a(n) = my(p=prime(n)); if(p==5, return(0), return(znorder(Mod(5, p^2))))
%Y Cf. A211241, A305332, A305333.
%K nonn
%O 1,2
%A _Felix Fröhlich_, May 30 2018