A070787 Number of triangles with sides whose squares are integers and with positive integer area and longest side of length sqrt(n).

0, 0, 0, 1, 2, 0, 0, 2, 1, 4, 0, 1, 3, 0, 2, 5, 5, 2, 0, 13, 0, 0, 0, 2, 9, 8, 1, 1, 9, 4, 0, 10, 0, 10, 2, 12, 11, 0, 3, 23, 14, 0, 0, 1, 13, 0, 0, 5, 5, 18, 5, 32, 18, 2, 2, 2, 0, 19, 0, 13, 16, 0, 1, 20, 35, 0, 0, 42, 0, 4, 0, 23, 24, 23, 9, 1, 0, 8, 0, 44, 10, 27, 0, 1, 48, 0, 9, 2, 27, 25, 3

Offset

1,5

Links

Table of n, a(n) for n=1..91.

A. Bogomolny, Sam Loyd's Geometric Puzzle

Example

a(13)=3 since the 3 triangles with sides {sqrt(13), sqrt(5), sqrt(4)}, {sqrt(13), sqrt(8), sqrt(1)} and {sqrt(13), sqrt(9), sqrt(4)} have areas 2, 1 and 3 respectively.

Crossrefs

Cf. A054875, A070783, A070784, A070785, A070786.

Sequence in context: A241067 A130457 A130454 * A033985 A216218 A122071

Adjacent sequences: A070784 A070785 A070786 * A070788 A070789 A070790

Keyword

nonn

Author

Henry Bottomley, May 07 2002

Status

approved