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%I #4 Mar 30 2012 18:57:36
%S 1,7,19,37,43,73,79,97,109,151,163,181,193,199,223,229,241,271,307,
%T 313,331,337,367,373,379,397,409,421,433,439,457,463,487,499,523,541,
%U 547,571,577,601,613,619,631,643,661,673,691,709,727,739,751,757,769
%N Monotonic ordering of set S generated by these rules: if x and y are in S and 5x+2y is a prime, then 5x+2y is in S, and 1 is in S.
%C See the discussions at A192476 and A192580.
%t start = {1}; primes = Table[Prime[n], {n, 1, 1000}];
%t f[x_, y_] := If[MemberQ[primes, 5 x + 2 y], 5 x + 2 y]
%t b[x_] :=
%t Block[{w = x},
%t Select[Union[
%t Flatten[AppendTo[w,
%t Table[f[w[[i]], w[[j]]], {i, 1, Length[w]}, {j, 1,
%t Length[w]}]]]], # < 2000 &]];
%t t = FixedPoint[b, start] (* A192594 *)
%t PrimePi[t] (* A192595 *)
%Y Cf. A192595, A192476, A192580.
%K nonn
%O 1,2
%A _Clark Kimberling_, Jul 05 2011
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