Template:Sequence of the Day for December 13

Intended for: December 13, 2011

Timetable

• First draft entered by Alonso del Arte on August 27, 2011 based on the write-up for December 12 with the appropriate adjustments. ✓
• Draft to be reviewed by October 13, 2011
• Draft to be approved by November 13, 2011

Yesterday's SOTD * Tomorrow's SOTD

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A033879: Deficiency of

n

.

{ ..., 14, 0, 28, −12, 30, 1, 18, ... }

The negative

a (n)

in this listing correspond to abundant numbers, the zeros correspond to perfect numbers and the positives correspond to deficient numbers. I’m choosing to start the listing here from 27 in order to get a better mix of abundant, perfect and deficient numbers.