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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
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, ...
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
Peter Kagey, May 18 2019
STATUS
approved