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A285261 a(2n-1) and a(2n) represent the smallest fraction a(2n-1)/a(2n) needing n unit fractions. 1

%I #11 Jan 11 2020 05:35:22

%S 1,2,2,3,4,5,8,11,16,17,77,79,732,733,27538,27539

%N a(2n-1) and a(2n) represent the smallest fraction a(2n-1)/a(2n) needing n unit fractions.

%C Huang Zhibin of China in April 2014 has verified that this fraction (27538/27539) needs 8 unit fractions.

%H Ron Knott, <a href="http://www.maths.surrey.ac.uk/hosted-sites/R.Knott/Fractions/egyptian.html">Egyptian Fractions</a>

%F a(2n-1) = A097049(n); a(2n) = A097048(n). - _Jon E. Schoenfield_, Jan 11 2020

%e For n=1, 1/2 = 1/2;

%e for n=2, 2/3 = 1/3 + 1/3;

%e for n=3, 4/5 = 1/2 + 1/4 + 1/20 and 4/5 = 1/2 + 1/5 + 1/10;

%e for n=4, 8/11 = 1/2 + 1/6 + 1/22 + 1/66;

%e for n=5, 16/17 = 1/2 + 1/3 + 1/17 + 1/34 + 1/51;

%e for n=6, 77/79 = 1/2 + 1/3 + 1/8 + 1/79 + 1/474 + 1/632;

%e for n=7, 732/733 = 1/2 + 1/3 + 1/7 + 1/45 + 1/7330 + 1/20524 + 1/26388;

%e for n=8, 27538/27539 = 1/2 + 1/3 + 1/7 + 1/43 + 1/1933 + 1/14893663 + 1/1927145066572824 + 1/212829231672162931784; etc.

%Y Cf. A097048, A097049.

%K hard,more,nonn

%O 1,2

%A _Robert G. Wilson v_, Apr 15 2017

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Last modified April 24 12:37 EDT 2024. Contains 371937 sequences. (Running on oeis4.)