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%I #6 Jan 03 2014 15:57:39
%S 2,4,7,11,17,19,31,37,41,47,71,79,97,127,151,167,191,197,257,337,397,
%T 607,677,797,1031,1217,1597,2437,2711,3191,4127,4871,4877,10847,43391
%N Monotonic ordering of set S generated by these rules: if x and y are in S and xy+3 is a prime, then xy+3 is in S, and 2 and 4 are in S.
%C See the discussions at A192476 and A192580.
%t start = {2, 4}; primes = Table[Prime[n], {n, 1, 40000}];
%t f[x_, y_] := If[MemberQ[primes, x*y + 3], x*y + 3]
%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, i}]]]], # <
%t 200000 &]];
%t t = FixedPoint[b, start] (* A192589 *)
%Y Cf. A192476 and A192580.
%K nonn,fini,full
%O 1,1
%A _Clark Kimberling_, Jul 05 2011
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