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A097049 a(n) = least numerator X of the proper fractions X/A097048(n) which need n or more terms as an Egyptian fraction. 1
1, 2, 4, 8, 16, 77, 732, 27538 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

These are the simplest proper fractions requiring n parts as an Egyptian fraction, where "simplest" means smallest denominator and the smallest numerator breaks ties: 1/2 2/3 4/5 8/11 16/17 77/79 732/733 ...

REFERENCES

R. K. Guy, Unsolved Problems in Number Theory, D11

LINKS

David Eppstein, Ten Algorithms for Egyptian Fractions

Hugo van der Sanden, Code

Hugo van der Sanden, Description of code

EXAMPLE

27538/27539 is the simplest rational that cannot be expressed as the sum of 7 or fewer distinct unit fractions. That is, no rational p/q requires 8 or more with 0 < p/q < 1, and either q < 27539 or (q = 27539 and p < 27538). - Hugo van der Sanden (hv(AT)crypt.org), Sep 14, 2010.

CROSSREFS

See A097048 for denominators.

Sequence in context: A051300 A001127 A051299 * A119490 A013174 A098204

Adjacent sequences:  A097046 A097047 A097048 * A097050 A097051 A097052

KEYWORD

nonn,more,frac

AUTHOR

Ed Pegg Jr. (edp(AT)wolfram.com) and Don Reble (djr(AT)nk.ca) Jul 21 2004

EXTENSIONS

a(8) from Hugo van der Sanden (hv(AT)crypt.org), Sep 14, 2010.

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Last modified February 16 19:23 EST 2012. Contains 205945 sequences.