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A070787 Number of triangles with sides whose squares are integers and with positive integer area and longest side of length sqrt(n). 4
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified December 5 13:38 EST 2016. Contains 278768 sequences.