Template:Sequence of the Day for July 13

Intended for: July 13, 2012

Timetable

• First draft entered by Alonso del Arte on April 29, 2011 as an almost verbatim copy of a write-up from November 1, 2010. ✓
• Draft reviewed by Alonso del Arte on July 10, 2011 ✓
• Draft approved by Daniel Forgues on July 12, 2011 ✓

Yesterday's SOTD * Tomorrow's SOTD

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A118372:

S

-perfect numbers.

{ 6, 24, 28, 96, 126, 224, 384, 496, ... }

Also called Granville numbers after the mathematician Andrew Granville. In October 2010, William Rex Marshall offered a much clearer explanation† of these numbers as well as a few more terms to list in the sequence (which includes the familiar 2-perfect numbers of A000396).

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† William Marshall, Who understands Granville numbers?, posting to SeqFan on Oct 28 2010.