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A309312 Areas of Heronian triangles that uniquely define the lengths of the triangle's sides. 1
6, 30, 42, 54, 66, 72, 114, 132, 150, 198, 204, 234, 294, 306, 378, 390, 408, 468, 486, 522, 570, 594, 648, 684, 726, 744, 750, 798, 816, 876, 984, 1014, 1026, 1110, 1170, 1218, 1254, 1290, 1332, 1350, 1368, 1428, 1494, 1518, 1548, 1554, 1590, 1734, 1770, 1782, 1806, 1938, 1950, 1974 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

These are not necessarily primitive Heronian triangles. The corresponding sequence for primitive Heronian triangles is neither a subset nor a superset of this sequence.

LINKS

Giovanni Resta, Table of n, a(n) for n = 1..10000 (first 500 terms from Jacob Vecht)

Wikipedia, Heronian triangle

EXAMPLE

A triangle with integer sides and an area of 42 square units necessarily has sides 7,15,20, so 42 is a term. 12 is not a term because an area of 12 could have sides 6,5,5 or 8,5,5.

CROSSREFS

Subsequence of A188158.

Sequence in context: A127662 A003062 A327157 * A101937 A101939 A290466

Adjacent sequences:  A309309 A309310 A309311 * A309313 A309314 A309315

KEYWORD

nonn,easy

AUTHOR

Jacob Vecht, Jul 22 2019

EXTENSIONS

Corrected 37th term "1248" to "1254".

STATUS

approved

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Last modified February 19 13:25 EST 2020. Contains 332044 sequences. (Running on oeis4.)