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A192587 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. 3
2, 3, 4, 5, 6, 7, 11, 13, 17, 19, 23, 29, 37, 41, 43, 67, 73, 101, 113, 137, 163, 173, 257, 401, 547, 677, 691, 821, 977, 1093, 1381, 2707, 3907, 5413, 5861 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

See the discussions at A192476 and A192580.

LINKS

Table of n, a(n) for n=1..35.

MATHEMATICA

start = {2, 4, 6}; primes = Table[Prime[n], {n, 1, 10000}];

f[x_, y_] := If[MemberQ[primes, x*y - 1], x*y - 1]

b[x_] :=

  Block[{w = x},

   Select[Union[

     Flatten[AppendTo[w,

       Table[f[w[[i]], w[[j]]], {i, 1, Length[w]}, {j, 1, i}]]]], # <

      50000 &]];

t = FixedPoint[b, start]   (* A192587 *)

CROSSREFS

Cf. A192476, A192580, A192586, A192588.

Sequence in context: A054010 A051948 A193461 * A174323 A103539 A174821

Adjacent sequences:  A192584 A192585 A192586 * A192588 A192589 A192590

KEYWORD

nonn,fini,full

AUTHOR

Clark Kimberling, Jul 05 2011

STATUS

approved

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Last modified October 23 16:46 EDT 2019. Contains 328373 sequences. (Running on oeis4.)