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%I #13 Mar 17 2024 16:05:33
%S 0,0,1,1,2,1,3,1,3,3,1,3,3,1,5,3,3,1,3,3,1,3,4,3,3,5,1,7,1,3,3,3,7,1,
%T 5,1,3,3,7,5,3,1,7,1,7,1,3,3,8,1,7,3,1,3,7,5,3,1,5,5,1,3,3,3,1,11,3,3,
%U 7,1,7,7,3,3,3,3,5,3,7,3,3,1,7,1,3,8
%N Number of moduli m such that (prime(n) mod m) = 2.
%C Except for the initial 0,0, this is column 2 of the array at A244740.
%H Clark Kimberling, <a href="/A244797/b244797.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A032741(A040976(n)). - _Ridouane Oudra_, Mar 17 2024
%e prime(5) = 11 = (2 mod m) for m = 3, 9 so that a(5) = 2.
%t z = 300; f[n_, m_] := If[Mod[Prime[n], m] == 2, 1, 0];
%t t = Table[f[n, m], {n, 1, z}, {m, 1, Prime[n]}];
%t Table[Count[t[[k]], 1], {k, 1, z}] (* A244797 *)
%Y Cf. A244740, A244796, A244798.
%Y Cf. A032741, A040976.
%K nonn,easy
%O 1,5
%A _Clark Kimberling_, Jul 06 2014
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