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 A192649 Monotonic ordering of set S generated by these rules: if x and y are in S and x^2-y^2>0 then x^2-y^2 is in S, and 1, 2, and 4 are in S. 3
 1, 2, 3, 4, 5, 7, 8, 9, 12, 15, 16, 17, 21, 24, 31, 32, 33, 39, 40, 45, 48, 55, 56, 60, 63, 64, 65, 72, 77, 79, 80, 81, 95, 111, 112, 119, 127, 128, 129, 135, 140, 143, 144, 145, 152, 159, 161, 175, 176, 185, 192, 200, 207, 208, 209, 216, 221, 223, 224, 225, 231 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS See A192645. LINKS Ivan Neretin, Table of n, a(n) for n = 1..10000 MATHEMATICA start = {1, 2, 4}; f[x_, y_] := If[MemberQ[Range[1, 700], x^2 - y^2], x^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, i}]]]], # < 700 &]]; t = FixedPoint[b, start] (* A192649 *) Differences[t] (* A192650 *) CROSSREFS Cf. A192476, A192646, A192650. Sequence in context: A335154 A278181 A232566 * A102363 A201816 A155900 Adjacent sequences: A192646 A192647 A192648 * A192650 A192651 A192652 KEYWORD nonn AUTHOR Clark Kimberling, Jul 06 2011 STATUS approved

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Last modified September 9 17:35 EDT 2024. Contains 375765 sequences. (Running on oeis4.)