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A154429
a(n) is the least k such that the greedy algorithm (for Egyptian fractions) on 4k/(24n+1) terminates in at most three steps.
2
2, 2, 2, 5, 3, 4, 13, 2, 2, 7, 5, 51, 4, 4, 5, 2, 3, 5, 5, 7, 5, 6, 2, 5, 11, 4, 3, 5, 5, 2, 2, 7, 4, 5, 29, 2, 2, 2, 5, 8, 4, 11, 2, 2, 6, 4, 11, 5, 3, 11, 2, 5, 5, 5, 7, 4, 37, 2, 3, 3, 4, 7, 5, 5, 2, 2, 17, 5, 5, 54, 2, 2, 2, 5, 7, 4, 11, 2, 2, 6, 5, 3, 4, 5, 10, 2, 7, 5, 5, 7, 5, 12, 2, 3, 10, 4, 7, 5, 5, 2
OFFSET
1,1
REFERENCES
J. Steuding, Diophantine Analysis, Chapman & Hall/CRC, 2005, pp. 39-40, 50.
LINKS
EXAMPLE
For n=3, the Greedy Algorithm gives 8/73=1/10+1/105+1/15330
MATHEMATICA
GreedyPart[q_Integer] := 0;
GreedyPart[Rational[1, y_]] := 0;
GreedyPart[q_Rational] := q - If[q < 0 || q > 1, Floor[q], Rational[1, 1 + Quotient[1, q]]];
SubtractShifted[l_] := Drop[l, -2] - Take[l, {2, -2}];
EgyptGreedy[q_] := SubtractShifted[FixedPointList[GreedyPart, q]];
terms := 200;
For[i = 25, i <= 24*terms + 1, i = i + 24, k = 2; While[Length[EgyptGreedy[4k/i]]> 3, k++ ]; Print[k]]
CROSSREFS
Sequence in context: A174960 A210239 A115253 * A333388 A174577 A194684
KEYWORD
nonn
AUTHOR
Matthew McMullen (mmcmullen(AT)otterbein.edu), Jan 09 2009
EXTENSIONS
More terms from Seiichi Manyama, Sep 21 2022
STATUS
approved