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%I #4 Mar 30 2012 18:57:35
%S 2,4,5,6,11,13,17,23,31,37,47,53,67,79,103,107,139,149,223,269,283,
%T 317,557,619,643,1699,2477,3343
%N Monotonic ordering of set S generated by these rules: if x and y are in S and xy+1 is a prime, then xy+1 is in S, and 2, 4, and 6 are in S.
%C See the discussion at A192580.
%t start = {2, 4, 6}; primes = Table[Prime[n], {n, 1, 10000}];
%t f[x_, y_] := If[MemberQ[primes, x*y + 1], x*y + 1]
%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 10000000 &]];
%t t = FixedPoint[b, start] (* A192582 *)
%Y Cf. A192476.
%K nonn,fini,full
%O 1,1
%A _Clark Kimberling_, Jul 04 2011
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