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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 (list; graph; refs; listen; history; text; internal format)
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

Ivan Neretin, Table of n, a(n) for n = 1..10000

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

Cf. A106430, A246429.

Sequence in context: A063930 A183170 A014411 * A143443 A139556 A191150

Adjacent sequences:  A247369 A247370 A247371 * A247373 A247374 A247375

KEYWORD

nonn,look

AUTHOR

Albert Lau, Sep 14 2014

STATUS

approved

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Last modified December 8 04:31 EST 2019. Contains 329850 sequences. (Running on oeis4.)