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A247372 List of b, where b is positive integer solutions of 1/a + 1/b = 1/c and a>b>c and gcd(a,b,c)=1, sorted by ascending a, then b. 4

%I

%S 3,4,10,5,21,6,14,24,7,36,8,18,55,30,9,44,60,33,10,78,22,65,11,52,105,

%T 70,39,12,26,112,136,42,13,60,119,80,14,102,171,30,126,85,48,152,15,

%U 180,68,133,210,90,51,16,114,34,140,95,17,168,253,76,198,230

%N List of b, where b is positive integer solutions of 1/a + 1/b = 1/c and a>b>c and gcd(a,b,c)=1, sorted by ascending a, then b.

%C For any positive integer m and n, a=m(m+n), b=n(m+n), c=m*n is an integer solution for 1/a + 1/b = 1/c.

%C See A106430 for list of a, A246429 for list of c.

%H Ivan Neretin, <a href="/A247372/b247372.txt">Table of n, a(n) for n = 1..10000</a>

%e 1/6 + 1/3 = 1/2.

%e 1/12 + 1/4 = 1/3.

%e 1/15 + 1/10 = 1/6.

%t aMax = 300;

%t Select[Sequence @@@ Table[{m (m + n), n (m + n), m n}, {m, Sqrt[aMax]}, {n, Min[m - 1, aMax/m - m]}], GCD @@ # == 1 &] // Sort;

%t %[[;;, 2]]

%Y Cf. A106430, A246429.

%K nonn,look

%O 1,1

%A _Albert Lau_, Sep 14 2014

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Last modified January 24 16:34 EST 2020. Contains 331207 sequences. (Running on oeis4.)