Template:Sequence of the Day for September 21

Intended for: September 21, 2011

Timetable

• First draft entered by Alonso del Arte on July 26, 2011 ✓
• Draft reviewed by Daniel Forgues on September 22, 2012 ✓
• Draft to be approved by August 21, 2011

Yesterday's SOTD * Tomorrow's SOTD

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A115020: Count backwards from 100 in steps of 7.

{ 100, 93, 86, 79, 72, 65, 58, 51, 44, 37, 30, 23, 16, 9, 2 }

This sequence is sometimes used to gauge the concentration ability of a patient with Alzheimer’s disease. The arithmetic is simple, but if short-term memory and concentration are compromised, a mistake is likely to occur at some point. Other decrements can be used for this purpose, with the alternative step preferably having no factor in common with 100.

Today is Alzheimer’s Awareness Day.