cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-1 of 1 results.

A140109 Quartets of prime x, composites y, z and S for Heron's formula.

Original entry on oeis.org

7, 15, 20, 42, 7, 24, 25, 84, 13, 14, 15, 84, 13, 84, 85, 546, 17, 8, 15, 60, 17, 9, 10, 36, 29, 20, 21, 210, 37, 12, 35, 210, 41, 9, 40, 180, 53, 45, 48, 1080, 73, 48, 55, 1320, 89, 39, 80, 1560, 97, 65, 72, 2340, 101, 20, 99, 990, 109, 60, 91, 2730, 113, 15, 112, 840
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Jul 10 2008

Keywords

Comments

Heron's formula (x+y+z)*(x+y-z)*(x+z-y)*(y+z-x)/16=S^2

Examples

			The quartets are: (7, 15, 20, 42), (7, 24, 25, 84), (13, 14, 15, 84), etc.

Crossrefs

Cf. A140385, A140391, A140384.

Extensions

This should be replaced by four linked sequences! As it stands it is not a proper sequence. - N. J. A. Sloane, Jul 11 2008
Showing 1-1 of 1 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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