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A244798 Number of moduli m such that (prime(n) mod m) = 3.

%I A244798 #8 Mar 17 2024 16:05:38
%S A244798 0,0,0,1,2,2,2,3,4,2,4,2,2,6,4,4,6,2,5,4,6,4,8,2,2,4,7,6,2,6,4,6,2,6,
%T A244798 2,4,6,10,4,6,8,2,4,6,2,7,8,10,10,2,6,4,6,6,2,10,6,4,2,2,14,6,8,10,6,
%U A244798 2,6,2,6,2,10,4,10,6,6,10,2,2,2,6,10,6,4
%N A244798 Number of moduli m such that (prime(n) mod m) = 3.
%C A244798 Except for the initial 0, 0, 0, this is column 3 of the array at A244740.
%H A244798 Clark Kimberling, <a href="/A244798/b244798.txt">Table of n, a(n) for n = 1..1000</a>
%F A244798 a(n) = A070824(A086801(n)), for n > 2. - _Ridouane Oudra_, Mar 17 2024
%e A244798 prime(5) = 11 = (2 mod m) for m = 3, 9 so that a(5) = 2.
%t A244798 z = 300; f[n_, m_] := If[Mod[Prime[n], m] == 3, 1, 0];
%t A244798 t = Table[f[n, m], {n, 1, z}, {m, 1, Prime[n]}];
%t A244798 Table[Count[t[[k]], 1], {k, 1, z}] (* A244798 *)
%Y A244798 Cf. A244740, A244796, A244797.
%Y A244798 Cf. A070824, A086801.
%K A244798 nonn,easy
%O A244798 1,5
%A A244798 _Clark Kimberling_, Jul 06 2014