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A192646
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First differences of A192645.
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6
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1, 1, 2, 3, 8, 5, 3, 15, 16, 5, 3, 72, 50, 7, 39, 16, 5, 3, 65, 49, 8, 39, 16, 5, 3, 72, 39, 16, 5, 3, 369, 1, 135, 185, 192, 39, 8, 8, 5, 3, 1, 368, 190, 369, 1, 46, 89, 47, 8, 130, 192, 39, 16, 5, 3, 17, 118, 185, 49, 48, 87, 8, 39, 16, 5, 3, 114, 192, 39, 16, 5, 3, 48
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OFFSET
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1,3
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COMMENTS
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Does this sequence include 1 infinitely many times?
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LINKS
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EXAMPLE
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A192645 = (1, 2, 3, 5, 8, 16, 21, ...) gives (2-1, 3-2, 5-3, 8-5, 16-8, 21-16, ...)
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MATHEMATICA
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start = {1, 2};
f[x_, y_] := If[MemberQ[Range[1, 5000], 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}]]]], # <
5000 &]];
t = FixedPoint[b, start] (* A192645 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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