

A306991


Number of primitive Heronian isosceles triangles with perimeter A308222(n).


0



1, 1, 1, 2, 2, 3, 2, 2, 3, 3, 5, 4, 3, 6, 4, 4, 5, 4, 8, 6, 9, 6, 6, 4, 8, 11, 8, 10, 6, 9, 9, 8, 14, 6, 15, 10, 11, 10, 8, 12, 10, 12, 18, 9, 12, 12, 20, 14, 8, 21, 15, 12, 16, 10, 23, 16, 21, 12, 12, 16, 18, 26, 18, 20, 12, 16, 18, 20, 29, 12, 21, 30
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OFFSET

1,4


COMMENTS

Records occur at indices of 1, 4, 6, 11, 14, 19, 21, 26, 33, 35, ... corresponding to perimeters of 16, 50, 98, 242, 338, 578, 722, 1058, 1682, 1922, ...


LINKS



EXAMPLE

For n = 6, the a(6) = 3 primitive Heronian isosceles triangles with perimeter A308222(6) = 98 have side lengths (24,37,37), (25,25,48), and (29,29,40), and areas of 420, 168, and 420 respectively.


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



