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a(n) is the common area of the n-tuple of Heronian triangles with minimal equal perimeter and equal area.

3

`%I #8 May 01 2020 08:11:40
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`%S 6,210,420,6720,49140,196560,4914000,91400400,348107760,4765400640,
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`%T 17057280240,68229120960
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`%N a(n) is the common area of the n-tuple of Heronian triangles with minimal equal perimeter and equal area.
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`%C Kurz's paper reports the first 10 values in a table on page 193, but for some reason the areas are multiplied by 4 (A204559) and the last two values are incorrect since correspond to n-tuples which are not minimal.
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`%C If n-tuples were sorted by area instead, a(2) would have been 168, corresponding to triangles (10, 35, 39), (14, 30, 40) with common perimeter 84.
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`%H Sascha Kurz, <a href="http://serdica-comp.math.bas.bg/index.php/serdicajcomputing/article/view/48">On the generation of Heronian triangles</a>, Serdica Journal of Computing Vol. 2 (2008), 181-196.
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`%H Giovanni Resta, <a href="/A334285/a334285.txt">n-tuples for n=1..12</a>
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`%e The first 3 entries and corresponding triangles:
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`%e a(1) = A = 6, p = 12, T = (3, 4, 5);
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`%e a(2) = A = 210, p = 70, T = (17, 25, 28), (20, 21, 29);
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`%e a(3) = A = 420, p = 98, T = (24, 37, 37), (25, 34, 39), (29, 29, 40).
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`%Y Cf. A198311, A204559.
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`%K nonn
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`%O 1,1
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`%A _Giovanni Resta_, Apr 21 2020
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