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A227611 Number of ways 2/n can be expressed as the sum of three distinct unit fractions: 2/n = 1/x + 1/y + 1/z with 0 < x < y < z. 4

%I #12 Sep 08 2021 01:12:10

%S 0,1,5,6,9,15,14,22,21,30,22,45,17,36,72,62,22,69,29,84,77,56,39,142,

%T 48,53,82,124,30,178,34,118,94,67,176,191,29,74,151,274,37,227,37,145,

%U 220,87,57,342,80,146,138,162,39,216,214,322,134,100,73,461,31,84,316,257,197,304,47,199,166,435,69,508,34,79,317

%N Number of ways 2/n can be expressed as the sum of three distinct unit fractions: 2/n = 1/x + 1/y + 1/z with 0 < x < y < z.

%C See A073101 for the 4/n conjecture due to Erdős and Straus.

%t f[n_] := Length@ Solve[2/n == 1/x + 1/y + 1/z && 0 < x < y < z, {x, y, z}, Integers]; Array[f, 75]

%Y Cf. A002966, A073546.

%Y Cf. A227610 (1/n), A075785 (3/n), A073101 (4/n), A075248 (5/n), A227612.

%K nonn

%O 1,3

%A _Robert G. Wilson v_, Jul 17 2013

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Last modified April 19 21:09 EDT 2024. Contains 371798 sequences. (Running on oeis4.)