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 A192598 Monotonic ordering of set S generated by these rules: if x and y are in S and x^2+2y^2 is a prime, then x^2+2y^2 is in S, and 1 is in S. 3
 1, 3, 11, 19, 139, 251, 379 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS See the discussions at A192476 and A192580. The start-set for A192598 is {1}. For results using start-sets {1,2}, and {1,2,4}, see A192612 and A192613. LINKS MATHEMATICA start = {1}; primes = Table[Prime[n], {n, 1, 20000}]; f[x_, y_] := If[MemberQ[primes, x^2 + 2 y^2], x^2 + 2 y^2] b[x_] := Block[{w = x}, Select[Union[ Flatten[AppendTo[w, Table[f[w[[i]], w[[j]]], {i, 1, Length[w]}, {j, 1, Length[w]}]]]], # < 30000 &]]; t = FixedPoint[b, start] (* A192598 *) CROSSREFS Cf. A192476, A192580, A192612, A192613. Sequence in context: A196174 A192591 A075226 * A028978 A082628 A279257 Adjacent sequences: A192595 A192596 A192597 * A192599 A192600 A192601 KEYWORD nonn,fini,full AUTHOR Clark Kimberling, Jul 05 2011 STATUS approved

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Last modified January 30 19:42 EST 2023. Contains 359947 sequences. (Running on oeis4.)