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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
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, 70, 39, 12, 26, 112, 136, 42, 13, 60, 119, 80, 14, 102, 171, 30, 126, 85, 48, 152, 15, 180, 68, 133, 210, 90, 51, 16, 114, 34, 140, 95, 17, 168, 253, 76, 198, 230
OFFSET
1,1
COMMENTS
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.
See A106430 for list of a, A246429 for list of c.
LINKS
EXAMPLE
1/6 + 1/3 = 1/2.
1/12 + 1/4 = 1/3.
1/15 + 1/10 = 1/6.
MATHEMATICA
aMax = 300;
Select[Sequence @@@ Table[{m (m + n), n (m + n), m n}, {m, Sqrt[aMax]}, {n, Min[m - 1, aMax/m - m]}], GCD @@ # == 1 &] // Sort;
%[[;; , 2]]
CROSSREFS
Sequence in context: A063930 A183170 A014411 * A143443 A139556 A191150
KEYWORD
nonn,look
AUTHOR
Albert Lau, Sep 14 2014
STATUS
approved