login
This site is supported by donations to The OEIS Foundation.

 

Logo

Annual Appeal: Today, Nov 11 2014, is the 4th anniversary of the launch of the new OEIS web site. 70,000 sequences have been added in these four years, all edited by volunteers. Please make a donation (tax deductible in the US) to help keep the OEIS running.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified December 22 07:03 EST 2014. Contains 252328 sequences.