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A192590 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. 1
2, 4, 5, 7, 11, 13, 17, 19, 23, 31, 41, 43, 59, 73, 79, 83, 89, 163, 233, 313, 353, 463, 929, 1249, 1409, 4993 (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..26.

MATHEMATICA

start = {2, 4}; primes = Table[Prime[n], {n, 1, 40000}];

f[x_, y_] := If[MemberQ[primes, x*y - 3], x*y - 3]

b[x_] :=

  Block[{w = x},

   Select[Union[

     Flatten[AppendTo[w,

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

      200000 &]];

t = FixedPoint[b, start]    (* A192590 *)

CROSSREFS

Cf. A192476, A192580.

Sequence in context: A350147 A110924 A335402 * A028289 A307872 A239510

Adjacent sequences:  A192587 A192588 A192589 * A192591 A192592 A192593

KEYWORD

nonn,fini,full

AUTHOR

Clark Kimberling, Jul 05 2011

STATUS

approved

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Last modified August 11 22:58 EDT 2022. Contains 356067 sequences. (Running on oeis4.)