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A283274
Areas of triples of primitive Pythagorean triangles having the same area.
1
13123110, 2203385574390, 2570042985510, 8943387723270, 826290896699730, 9381843970167926138271390
OFFSET
1,1
COMMENTS
The generators for the currently known triples are:
a(1): (5,138),(38,77),(55,78): Charles Shedd, 1945
a(2): (55,3422),(61,3306),(266,2035): Randall L Rathbun, 1986
a(3): (143,2622),(869,1610),(1817,2002): Randall L Rathbun, 1986
a(4): (198,3565),(1166,2201),(2035,2438): Randall L Rathbun, 1986
a(5): (731,10434),(1122,9077),(2465,7238): Dan Hoey, May 18 1990
a(6): (352538,2999447),(1931103,2398838),(3063347,3215070): Duncan Moore, Mar 01 2017
The generator (a,b) gives the Pythagorean triangle (b^2+a^2,b^2-a^2,2ab) with area ab(b^2-a^2).
REFERENCES
R. K. Guy, Unsolved Problems in Number Theory, D21.
EXAMPLE
The generators of a(1) give the 3 Pythagorean triangles (19069,19019,1380), (7373,4485,5852) and (9109,3059,8580). They have the areas 19019*1380/2 = 4485*5852/2 = 3059*8580/2 = 13123110 = a(1).
CROSSREFS
Cf. A009111.
Sequence in context: A210412 A048937 A257269 * A343083 A342687 A342688
KEYWORD
nonn,hard,more
AUTHOR
Duncan Moore, Mar 04 2017
STATUS
approved