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%I #10 Nov 06 2018 13:16:27
%S 1,2,3,5,7,8,10,11,13,14,15,17,19,20,21,23,25,26,27,29,30,31,32,34,36,
%T 37,38,39,40,42,44,46,47,48,50,51,52,54,55,56,58,59,61,62,63,64,66,69,
%U 70,71,72,74,75,77,78,79,81,82,83,84,85,87,89,91,92,93
%N Ranks of primes p when all primes p and products 3*p are jointly ranked.
%H Clark Kimberling, <a href="/A298863/b298863.txt">Table of n, a(n) for n = 1..1000</a>
%e A105585 = ordered sequence of primes p and products 3*p: 2, 3, 5, 6, 7, 9, 11, 13, 15, 17, ... in which primes occupy ranks 1,2,3,5,7,8,10,...
%t z = 1000; u = Prime[Range[z]]; w = Take[Union[u, 3 u], z];
%t p[n_] := If[MemberQ[u, w[[n]]], 0, 1];
%t Take[w, z]; (* A105585 *)
%t t = Table[p[n], {n, 1, z}];
%t Flatten[Position[t, 0]]; (* A298863 *)
%t Flatten[Position[t, 1]]; (* A298864 *)
%Y Cf. A000040, A105585, A298864 (complement).
%K nonn,easy
%O 1,2
%A _Clark Kimberling_, Feb 13 2018
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