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A308222 Numbers that are the perimeter of a primitive Heronian isosceles triangle. 1
16, 18, 36, 50, 64, 98, 100, 144, 162, 196, 242, 256, 324, 338, 400, 450, 484, 576, 578, 676, 722, 784, 882, 900, 1024, 1058, 1156, 1250, 1296, 1444, 1458, 1600, 1682, 1764, 1922, 1936, 2116, 2178, 2304, 2450, 2500, 2704, 2738, 2916, 3042, 3136 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A primitive Heronian triangle is a triangle with integer sides and area, where the side lengths do not share a common divisor.

LINKS

Table of n, a(n) for n=1..46.

Math Stack Exchange user "George", Semiperimeter of isosceles Heronian triangles.

Wikipedia, Isosceles Heronian triangles.

FORMULA

a(n) = 2*A096033(n+2) (conjectured).

EXAMPLE

Table illustrating first six terms of the sequence:

  perimeter |   sides    | area

  ----------+------------+-----

      16    |  (5,5,6)   |  12

      18    |  (5,5,8)   |  12

      36    | (10,13,13) |  60

      50    | (13,13,24) |  60

      50    | (16,17,17) | 120

      64    | (14,25,25) | 168

      64    | (17,17,30) | 120

      98    | (24,37,37) | 420

      98    | (25,25,48) | 168

      98    | (29,29,40) | 420

CROSSREFS

Cf. A046790, A096033, A096468.

Sequence in context: A334586 A333917 A335248 * A278471 A223588 A183401

Adjacent sequences:  A308219 A308220 A308221 * A308223 A308224 A308225

KEYWORD

nonn

AUTHOR

Peter Kagey, May 16 2019

STATUS

approved

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Last modified November 28 19:48 EST 2021. Contains 349415 sequences. (Running on oeis4.)